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Horse Power Calculator
This program calculates approximate rear wheel horsepower based on actual vehicle weight (including driver), and quarter mile elapsed time and trap speed.There are two formulae. One uses weight and e.t, the other uses weight and speed. This program does both and averages them.The "Approx Engine HP" assumes 25% drivetrain losses. Obviously, there are a lot of variables unaccounted for.
| Car Weight (with driver) | |
| Elapsed Time | |
| Trap Speed | |
| HP to Rear Wheels | |
| Approx. Engine HP | |
For those of you who might not know how to work this H.P. calculator, click the "Reset" button to restart the process. Type in your vehicles total weight with you in it. (There are many web sites that have your vehicles weight posted on them.) Then type in the E.T. (elapsed time) that is the time that it took you and your vehicle to travel the distance of 1/4 mile. Then type in the Trap Speed, the MPH/speed that you achieved when you passed the 1/4 mile finish line mark, then click on the "Calculate" button to see your results.
HP Calculator script courtesy of
fastcoolcars.com
Q: Does BAD-ASS Racing build stock replacement engines for daily drivers or should I just go buy a "crate motor"?
A: Yes, we build stock replacement engines and most of the time we can meet or beat the "crate motor" prices and you'll end up with a better engine! Our bone stock early and late model replacement engines get only top quality, name brand parts and they are built specially for you. We tailor your engine for your specific application. Have a truck that needs a little more balls for pulling that boat trailer? Want an engine specifically for gas mileage? Want a stock engine with just a little more cam for "that sound"? We can do it! When you buy a crate motor, you get what you get. It is a general engine designed to cover a lot of applications and that isn't always the best way to go. An F-100 1/2 ton truck pulling a trailer is going to need a different engine than an 84 Mustang GT, even though they both have 5.0 engines... they're not the same! Crate motors sound good because they're brand new at an attractive price. Well, keep in mind, crate motors aren't always what they're cracked-up to be. The GM engines have plastic timing covers and the blocks are thinner among other things. I see a lot of returned and defective crate motors lying around the dealerships. Some guy's say, "yeah, but for $1,350.00, I got a 300 Horsepower 350!" Hey... that's no big deal, I can build the same thing with as much (or more) horsepower and torque for the same price and it will be a stronger engine! Remember, horsepower is one thing and torque is another. Going back to the F-100 and Mustang GT examples I gave earlier, the truck might have less horsepower but more torque for towing and the mustang might have a higher horsepower rating but less torque. It's all relevant to the application, which you don't get with a crate motor. It's no brain surgery getting horsepower out of an engine and 300 to 350 horsepower is no problem what so ever out of a "stock" engine! As for that 502 big block? First off, that engine comes as an un-assembled "kit" that you have to put together and second off, 502 horsepower out of 502 cubic inches isn't anything to brag about! My street 454's make over 550 horsepower for about the same price as that un-assembled 502 and my 490 cubic inch "street beast" engines make almost 600 horsepower and it's bullet proof! TOP
Q: How much would it cost to build something like a 500 Horsepower small block?
A: First, getting a REAL honest to goodness 500HP out of a pump gas street engine isn't an easy thing to do unless you really know what you are doing (which we do) or you are planning on running a supercharger or nitrous. A true 500HP engine will propel a car into the upper 10 second times in the quarter mile (on average), and really, how many street trim 10 second cars do you see running around? Not many I'll bet. There sure are a lot of people that "claim" they have 500HP, but when they hit the track and run a 14 second et, the excuses start flying like a flock of birds why they couldn't pull-off a 10 second, (or even an 11 second) time slip, and the reason they couldn't pull a 10 second time is simple, thay ain't really making 500HP.
Second, always remember this, horsepower is cheap, strength costs money. It's a no brainer to pop a set of 13:1 pistons, a large cam, port-out a set of heads and a few other tricks to get a lot of horsepower out of an engine. Horsepower is a no brainer. It's a simple matter of increasing cylinder pressure, which can be achieved by increasing the static compression, increasing the flow of the heads, or stuffing more fuel and air into the cylinders via a supercharger, or creating a mass of expansion and heat in the cylinders with a shot of nitrous, which is easy and cheap, but will it last? Not if the parts aren't strong enough to handle the stress and heat! The key that needs to be followed is matching the parts so they work together, and building it strong so that it will hold-up under the heat, stress and RPM it's going to be put through. I can easily build a 500 horse small block or even a 750 horse small block for about $2,500 but it ain't going to last but only a few minutes! It must be built with strong parts or it's going to end-up as a large puddle of oil and twisted metal in the middle of the road. Strong, quality parts aren't cheap. There are ads in magazines that offer 350's and even 383 stroker motors with 450 horses for about $3,500, but when you look at what's in them, most of the parts are just crap. They use plain old cast, stock pistons, stock "reconditioned" rods, (which adds nothing to the strength). They use cast iron stock or low priced (and low quality) after market heads, stock cranks, re-used main bolts, head bolts and rod bolts and so on. Remember this, the ONLY thing holding your engine together are the bolts, so they'd better be the best you can buy! There are too many variables to put a single price on an engine, unless it's a generic "crate motor" and with those, you get what you get, with no choices or options. That's why we don't pre-build any "generic" engines.
Third; when comparing engine prices to horsepower, remeber this, you don't pay for horsepower, you pay for quality and strength! Here's a good comparison. A 750HP small block Chevy Sprint Car engine is about a $15,000 engine, and that's including the fuel injection system! The same 750HP small block in Nascar trim suddenly becomes a $40,000 engine, and they don't even have a $5,000 fuel injection system! So why is the Nascar engine so much more expensive for the same amount of power? That's simple. Because the Nascar engine is MUCH stronger and lighter. A Sprint car only has to run a few laps a night to get by, and there's only a little bit of sponsorship money behind the car. A Nascar has to run at 9,000RPM for 400 or 500 miles at a time with millions and millions of contengency and sponsorship money behind the car, so they can't afford to have a failrue because a part couldn't take the stress. The comparison has the same princibles in ANY engine when comparing prices, including street engines. Our engines are built "Bad Ass", and they'll make the power we say they'll make! They are built strong and designed to withstand the kind of abuse that you want to put it through without falling apart. After all, it's our reputation and ass on the line. So now you can see, there are lots of options that dictate how strong an engine will be and what it will cost, and it usually doesn't have anything to do with how much power it makes. Always remember, it's the quality and strength you're paying for... not the horsepower.TOP
Q: How can I get more power out of my engine and still pass smog?
A: I get this question a lot and you only have a couple of options. Whenever you increase horsepower, you are automatically going to increase the amount of hydrocarbons coming out the tail pipe and that is what the smog station is looking for. You can opt for a whole bunch of expensive add-on's such as a computer chip, a larger Mass Air flow, a "Cat back" exhaust system, a K&N air filter and so on, but what you get for your dollar, as far as really being able to "feel" the so called added horsepower, isn't much at all. You might spend $350 on a chip, $60 on a K&N air filter, $175 on a larger Mass Air Flow and $400 on a "Cat Back" exhaust system and maybe feel a slight difference, so that's about a thousand bucks for maybe 25 or 30 extra horsepower if you're lucky. Headers are always a good choice if there is a set available for your vehicle that carries a CARB (California Air Resourses Board) exempt number but don't expect to feel like you now have a race car with merely a set of headers bolted on, 'cause you probably won't feel much difference at all with those either, but still, I think they're a good choice.
There are basically two options you have that will make a substantial difference in power AND still be smog legal.
1: Bolt-on a small nitrous oxide system and go. That one'e pretty simple and contrary to what you might have heard from "experts" who have probably never even owned a nitrous system, it doesn't wipe out engines if it is used in moderation and set-up correctly. This is probably the easiest, cheapest and fastest bang for the buck you can do and still be able to pass smog, and if you keep the power level down to about a 75 - 125 HP shot, you should be fine, but if you go trying to add a 450HP fogger system to your stock engine... kiss it good by the first time the button is pushed. You just can't do that to a stock engine. So, would you rather spend about a grand on all of those little bolt-on goodies and gain maybe 30 horsepower (if you're lucky) or bolt-on a small nitrous system and have enough power to blow the doors off of just about everyone in your neighborhood?
2: The next best thing as far as adding instant horsepower and still being "smog legal" is bolting-on a small supercharger. I'm not talking about a roots type blower like a 6-71 or 8-71 you see sticking out of some car's hoods... I'm talking about a centrifigual supercharger such as a Vortech, Paxton, ATI ProCharger, Powerdyne, etc. Most of them offer bolt-on kits for your application and most also carry a CARB exempt number. Some even have certificates that say it won't void a car's warranty if the boost level is kept down to about 4 or 5 psi. These kits aren't cheap though and can easily run anywhere from $2,000 on up to about $4,000, but expect about a 75 to 200 HP increase on pump gas and everything fits under the hood. It's instant power, 24-7-365 with no bottles to refill or buttons to push. You just mash the gas and hang-on! These superchargers are also a great choice for trucks (both 2 WD and 4 WD) that tow trailers or pull steep hills up in high altitudes. No more bogging down or trying to keep up with the flow of traffic while pulling that heavy trailer once you've bolted one of these on.
Those are the 2 best ways that I can recommend for a real horsepower increase on a smog legal engine. You can do all of that other expensive bolt-on stuff if you want and "run with the pack" like everyone else or you can blow their doors off. Just remember, I didn't built my reputation on building Bad-Ass engines and nasty cars that "ran with the pack"... mine lead the way! TOP
Q: How high will one of you BAD-ASS Engines rev?
A: The question should never be "how high will it rev" but rather, "At what RPM does it make it's peak horsepower and is the engine built strong enough to run at it's peak power making RPM?". A bone stock Chevy 350 out of say, a 69 Caprice, can rev to over 7,000 RPM without coming apart. Oh, it quit making power way back at around 4,500 RPM due to the restricted heads, anemic cam, small carb and so on, but if you keep it floored long enough and the valve float isn't too bad, it'll go right-on up to 7,000 or more RPM. Small block Ford's can come close to that but with the small rod bolts they use, they are more limited in RPM and the engines usually come apart between 6,000 and 7,000 RPM. How high an engine can rev is one thing, where it makes its power is an entirely different thing. If you build an engine with top of the line components, like one of ours, it can safely rev to 8,000+ RPM but it may peak it's power curve at 6,500 RPM or more, or maybe less, that's all dependent on the heads, the cam profile, stroke, exhaust system, intake system, etc. So what happens if you take it past its peak power curve? It loses power dramatically! You can lose 50 or even 100+ HP by revving an engine over it's power making limit, so why would you want to do that. Scenario: You're racing this guy and while you're busy trying to impress everyone around as to how high your engine can rev, and in the mean time, taking it past it's peak power making point while the guy along side of you has shifted to the next gear within his power range and is beginning to pull away from you, that ain't very impressive. So, never ask "how high will it rev"... because it will most likely rev beyond it's power making capabilities. Always ask, "what RPM does it make it's peak HP and torque at". TOP
Q: What's the best combo to go with for my engine?
When you buy a Bad-Ass Engine, you are buying something built specifically for your particular vehicle and needs. It is built with care and with decades of hard learned experience behind it. We get hundreds of e-mails a week asking "what's the best cam for my engine", "what's the best heads to go with", "what's the best compression and pistons", what's the best carb" and so on. We can't really tell you what the best cam, carb, heads or whatever may be because there are just too many variables that have to be taken into consideration. We can't just say off the tops of our heads what will work the best without lots of time and thought involved. On another note, we don't really give out specifics like that unless your are a customer. If we did, we might as well close-up shop because we are just giving away everything that took us years to learn, not to mention the countless engines we've had to build and test, plus all of the money we've spent on all of that the past 3 decades. Giving free info out like that so other people can try to do it themselves doesn't put food on our plates. It would be like going to your doctor when you are sick and asking him to tell you what is wrong with you and what the best medication would be to make you well again and not expecting to pay him for his years of schooling and experience, or asking your CPA what's the best way to do your books and taxes but wanting to do it yourself. That's why you go to a doctor or a good CPA, because he knows what he is doing and knows the best way to go with first time. We are the same way. You buy a Bad-Ass Engine because you KNOW that you are getting the best you can buy and with the best combination of parts that will do the job you need, as well as endure the abuse you want to give it and last a long time. Like we say several places in this web site; "Horsepower is cheap. You don't buy horsepower, you buy strength"! A high horsepower engine isn't very good if it's built weak with cheap parts or has crappy machining. It simply won't last. Why bother spending money on something like that? Hell, you can go buy a mediocre crate motor if you want that. An engine built strong, that will last is obviously a better choice. Good, strong parts aren't cheap and neither is good machining. There's a big difference between an engine advertised in a magazine or on ebay boasting about making 400+ horsepower for only $2,995 and an engine that not only makes that kind of power but is built with good parts and care and will last a long time. We won't build half assed or weak engines, we ONLY build strong, powerful engines that will last so you can blow the doors off all your friend's cars who made the mistake of buying something other than a BAD-ASS Engine! TOP
Q: Which is better, a solid, hydraulic or roller lifter cam?
A: This all depends on what you're doing with the engine. There's no substitute for roller cams period. The name of the game is flow.. Heads don't flow if the valves are shut. Roller cams have a lightning fast ramp speed. The valves snap open and slam shut much faster than flat tappet cams which means the valves are open for a longer period of time. While a slower ramped cam, like a solid or hydraulic, is beginning to open the valve, the steep lobes of a roller cam (in retrospect) already have its valve wide open, thus more flow into the cylinder. On the same note, the slower ramped cam needs to start closing the valve, and while it's closing, the roller cam is still wide open and still flowing until the very last second and SNAP! It slams shut. The aggressive profile and ramp (lobe) speed of a roller cam also has its drawbacks. A higher lift and faster ramp speed needs stiffer valve springs. Stiffer valve springs require screw-in studs or you'll rip the stock, pressed-in studs right out of the head. Stiffer springs also increase the load on the push rods, so heavy duty push rods are needed. High lift cams add more movement and friction to the rocker arms, so roller rockers are pretty much a must. Most billet steel roller cams require using an aluminum/bronze distributor gear which is very soft and doesn't last very long (a month maybe?). Just like Newton's law, for every action, there is a reaction, engines are the same way. Increase the load in one place and you'll surely increase the load in other places.
Technology and metallurgy are changing. It use to be that a hydraulic cam wouldn't be very good for a hot street or a mild race engine when in fact, they perform very well! As long as good matching valve springs are used with a good quality set of lifters, there's no reason a hydraulic cam can't do well on the street or the track and if someone tells you different, have them tell that to the guys running hydraulic cams at well over 7500 RPM in 11 and 12 second street cars!
Solid lifter cams are always a good choice for a hot street or race engine. They usually have faster ramps (lobes) than hydraulic cams but not as fast as roller cams. They also usually need a stouter spring than a hydraulic cam but not nearly as stiff as a roller cam. They're kind of the middle of the road between the two. Forget about those lame wives tales about solid lifters always going out of adjustment! That's just not true! The ONLY way the adjustment (lash) can change is if something is either wearing out or going bad, period! If a rocker stud starts pulling out, the lash will increase. If the tip of the valve is getting hammered or mushroomed, the lash will increase. That's what lash caps are made for. If the tip or the cup of the rocker arm starts to wear out, the lash will increase. If a push rod bends or wears out one (or both) of the tips, the lash will increase. If the lifter is getting cupped or the cam is going flat, the lash will increase. If a valve seat "sinks" or recesses, then the valve is actually lifting or sitting higher, the lash will decrease. No matter how you slice it, if a solid lifter cam keeps going out of adjustment, something is seriously wrong! Most of the time it was just a wives tale being spread by someone who's probably never even ran a solid lifter cam or had a piece of junk engine that was falling apart. TOP
Q: How much compression can I run and still use pump gas?
A: This is a good one with no single answer. The key here is cylinder pressure, not compression! Cylinder pressure is controlled by valve timing (overlap), not the piston. Although bore, stroke, compression height, deck height and combustion chamber size, among others, have a great deal to do with the whole ball of wax, they don't dictate the actual working or "effective compression" or cylinder pressure of an engine. Example: two identical engines both with 9:1 "static compression". The only difference is in the cam profiles. One has no overlap with particular valve timing on the intake valve, and the other has a lot of overlap with a completely different intake valve timing. Overlap is the time in which both valves are open as the piston pushes exhaust out and starts to suck new fuel and air into the cylinder. When the exhaust valve is closing and the intake valve begins to open, there is a time (on high performance and race cams) where both valves are actually open at the same time. A piston can not make cylinder pressure if a valve (or valves) are open, whether individually or at the same time. As the piston goes back down and starts to suck-in a new charge of fuel and air into the cylinder, it is also still sucking exhaust back in, as long as that exhaust valve is still open. Some of the air and fuel (charge) is being pushed back out either of the open valves, thus creating that "rumpity bump" sound everyone likes so much, but by letting some of the charge escape, there is less there to suck-in and/or squeeze, thus creating less pressure. Overlap and valve timing on performance cams also decrease the velocity of air feeding the engine at lower RPM's, which is why cams "come alive" at higher RPMs. Overlap also causes a decrease in manifold vacuum, making throttle response sluggish. When you have too much overlap, you end-up with a dog for an engine that has no throttle response. This is what's known as being over-cammed. Lots of engines out there are over cammed. This is why they sound good to some people, but are complete turds off the line or when they hit the quarter mile.
If you did a compression test on either of these two 9:1 static compression engines, the engine with no overlap (or even negative overlap) would probably have about 140 -150psi or so in the cylinders. The engine with more overlap may only have 100 psi or so, depending on how much overlap the cam has, how narrow the lobe separation angle is, and what the valve timing is (when the intake valve opens and closes, and when the exhaust valve opens and closes). Some racing engines with 13:1 or so compression only have 125psi or so of cylinder pressure when a compression test is done. That's less than what grama's old beat-up car with over 100k miles on it is supposed to have! It just means that the cam has a ton of overlap and has valve timing designed to work on a "scavenging" princible, which actually increases cylinder pressure at higher RPMs. This is why race engines have "power bands" and come alive at higher RPM's. It's because the cylinder pressure increased as the engine came-up in RPM, which resulted in more horsepower. So, you can run 92 octane pump gas on 11:1 compression with the right cam but 9:1 could ping (detonate) with the wrong cam. Way back in the early 80's, Crower had a fuel economy kit that was designed to run on pump gas (for gas mileage) yet had a compression ratio of 14:1!! Really! It's all in the cam profile. It worked but never caught-on so they dumped the idea. Bottom line, cylinder pressure, not compression dictates what kind of fuel you'll need to run.
On another note, consider this: There are crap loads of older 68 & 69 302 Z/28's that came stock with 11:1 compression. The 63 and 64 365HP and 375HP 327 Vette's came stock with 11.25:1 compression. Shelby's, Cobra's, big block Chevelle's, 340 and 440 Six Pack and "magnum" Chrysler's came with everything from 10:1 to over 11:1 depending on the options. BOSS 302's and BOSS 429's, the 70 351-4V Mach 1's and MANY, MANY more cars ALL came stock with 10:1 to over 12:1 compression on some limited models and they all ran premium pump gas. Many of these cars are still running today on today's fuels. Just so ya know, brand new Ferrari's, Lamborghini's, Non turbo Porsche's, M3 and M5 BMW's and so on all come stock with 11:1 compression and some even slightly higher. With the advent of computers and knock sensors, the timing can be controlled and detonation (pinging) can be kept at bay. Ignition timing also helps control cylinder pressure. Eitheer way, whether it's the cam timing or the ignition timing, the bottom line is, it ain't the "compression ratio" that dictates whether you can or can't run pump gas, it's how much cylinder pressure the complete package makes as to whether you can or can't run pump gas.TOP
Q: What about octane boosters, Av. gas or race fuel?
A: The higher the octane rating, the slower and colder the fuel burns. If you run too much octane in your engine, it won't run very well because the burn is way too slow. If the octane is too high, the piston might already be at bottom dead center (BDC) and the fuel might still be burning! If the octane is too low, the fuel will burn too fast and too hot which causes detonation and leads to sure-fire engine damage! Aviation fuel is another no no. A famous engine builder (top fuel engines) told me a story about an engine that was in his shop that had major melt down in the cylinders. He said, "Arron, av. gas is for air planes! Where do you see airplanes? Up in the sky! Do you see cars up in the sky? No! How does your car run when you're up in the mountains? Yeah, like crap! There's no oxygen up there. Aviation fuel is designed to be run in a low oxygen atmosphere. What happens to that cutting torch flame when you add oxygen to it? Yeah, the flame gets hotter and turns blue! What do you think happens to an engine in a high oxygen atmosphere burning aviation fuel? Look right here at this engine and you'll know!"
He made a good point.
Octane boosters of today are usually made of two things, either alcohol of some sort of flame retardant. Alcohol works OK I guess but the flame retardant stuff that turns your sparkplugs red? Don't go there! The object is to burn all of the fuel in the cylinder, not put it out! The old octane boosters, the good ones, are all outlawed. The best that I can remember was something called Aniline Oil. This stuff worked great but you had to use a fresh air mask and wear gloves because it displaces oxygen. If you spilled it on your skin, it would turn that area blue! TOP
Q: Is it OK to run aluminum heads on the street?
A: Of course! Most foreign cars have been running aluminum heads for decades. What gave aluminum heads a bad rap was the Chevy Vega and the way after market aluminum heads were surfaced. Aluminum expands almost twice as much as cast iron. A couple of decades ago (boy I feel old), all heads were machined the same way, with a slightly rough surface to grip the head gasket. Well, aluminum heads, with their greater expansion rate were actually skating across the head gaskets and the little machine marks left by the bits would cut, or wear through the gaskets. Now, when you look at aluminum heads, the deck surface is almost totally smooth so as the head expands, it doesn't scrape into the head gasket. The big advantage with aluminum heads, besides being almost half the weight of cast iron, is that they run cooler and allow you to run a little more compression (or cylinder pressure) on the same gas without pinging or detonating. TOP
Q: Why do I see a lot of crate motors in hot rods these days?
A: This one is beyond me! You spend all of your precious time and efforts in building a great car, going over every detail to make it just the way you want it and then throw a generic crate motor in it? I see this all of the time. I have seen $200,000+ roadsters in pristine, "invite only" shows that have custom, one of a kind made frames, one of a kind billet wheels, hand made bodies that have thousands of hours in the making and you look under the hood and there's a dog gone crate motor sitting there with a bunch of billet stuff bolted on it!! Is that all they think their car is worthy of? A crate motor? Hot rodding used to be about making power and building "custom" engines. The engine is the very heart and soul of hot rodding. It's not about who can spend the most money on the rest of their car. These guy's won't flinch at dropping over $5,000 or $10,000 on a set of one of a kind billet rims, or dropping $50,000 in a paint job but they'll whine and cry about spending $ on a custom built engine. People can brag and bench race all they want, buy crate motors and bolt-on all of the shiny accessories they can get their hands on and they're still going to have nothing more than the same, motor that some other guy has in his work truck, and they'll still get their doors blown-off by the guy's who cared enough to buy a REAL Bad-Ass engine. There's nothing "Bad-Ass" about a crate motor. TOP
Q: Do those fancy split tip sparkplugs really work?
A: No. Electricity follows the path of least resistance. It has nothing to do with a split tip or a fancy U groove! The sparkplug does one thing only. It acts as the grounding source for the ignition's electricity and that's it, period, end of story. The only difference with a sparkplug is that there is a gap in the current path. The size of the spark is dictated by the voltage and amperage output of your coil, and the output of your coil is dictated by the saturation (dwell) time of your ignition system. You'll hear claims like, "it made more horsepower" or "I got better gas mileage". Well of course they did! Their engine needed a tune-up or they wouldn't have tried the new plugs in the first place! ANY engine would get better gas mileage and more horsepower after a tune-up!
What split tipped plugs can do is promote pre-ignition and/or detonation. How? Try this, take a hanger and try to heat it up with a cigarette lighter. Oh yeah, it gets hot, but not hot enough to glow cherry red. Now take a paper clip and heat it up with the same lighter. It gets hotter faster and glows cherry red! It's simple, it takes less heat to heat-up smaller objects. What do you think those tiny little pieces of split tip electrodes are doing in your engine? Now add more compression and heat (like in a race engine) and they act like a dog gone glow plug... detonation... ka-boom! Just about in that order.
Now there ARE things you can do to help the burn in the cylinder with the spark plugs (which actually will increase power), such as indexing them. It's easier to show you how to do this than to tell you, but here's a quick overview so you'll at least get the basic idea. Indexing a spark plug puts the open end of the gap towards the intake valve. This way when it sparks, the ground strap isn't in the way, blocking the flame path. It exposes the open end of the gap to the fresh air / fuel mixture coming through the intake valve and into the cylinder, which helps light the cylinder faster and more evenly. Better burn = more power. There's a little more to it, and like I said, it is easier to show you than it is to write it out. You start by marking the outside of the spark plug with a Sharpie pen in line with the back side of the ground strap. When you screw the plug into the head, try to get the mark to point away from where the intake valve would be. This puts the back side of that ground strap pointing at the exhaust valve or the back side of the combustion chamber, which in turn points the open-end of the gap at the intake valve and into the open area of the cylinder for a clean, unobstructed flame path. They actually make special crush sleeve "washers" that go onto the spark plugs so you can snug the plug up, yet continue to turn it to "index" the plug to where you want it.
Obviously heat range has a little to do with how a plug fires too, but that subject is always a mystery to many people. Many guy's run way too cold of a plug in their performance engines because "their buddy" told them to. I always get a kick out of that. If I had a nickel for every time I heard someone say "my buddy told me to do that" for something that totally didn't work, I'd be a millionaire! Anyway, cold plugs don't retain enough cylinder heat to burn off deposits and they foul quickly, thus making your engine run like crap. A hot plug runs cleaner because nothing can stick to it. When you clean greasy dishes in your sink, you use hot water to cut the grease, right? Well, spark plugs aren't much different. Now, the wives tale is that a hot plug will make your engine run hot, and that is about as ass backwards as you can get. Hold a new spark plug in your hand. is it hot? NO! So how can something that isn't hot, and that doesn't create heat make your engine run hot? It can't. The cylinder temperature inside your engine heats the plug up, not the other way around. All a hot or cold plug means is how hot the core temperature (or running temperature of THE PLUG) will be. If you run too hot of a plug, it will allow it to retain too much heat and it will begin to melt off the electrode, thus causing the engine to misfire. The trick is, you want the hottest plug you can possibly run WITHOUT melting off the electrodes.
Now, a cool trick for nitrous and blower guy's is when you run a plug that is on the hot side, you can actually use the plug as a "safety fuse". In other words, if your plugs run just under the melting point, then if you have the misfortune of leaning the engine out, (THE worst thing you can do to a nitrous or supercharged engine), it will increase the plugs core heat and melt off the electrode, thus causing the cylinder to not fire anymore. No more fire = no heat. No heat means no lean-out melt down. Obviously it takes time and testing to figure out exactly what to run, but these tips give you some good ideas and starting points anyway.TOP
Q: What should I gap my plugs at?
A: What dictates the width of a spark plug gap is both the amount of voltage and amperage of your ignition system as well as cylinder pressure and air / fuel mixture density. The rule of thumb is that a smaller gap will yield a short, intense spark and will usually make the engine real responsive but not very well at higher RPMs. A wide gap creates a longer spark arc but without sufficient "juice" from your ignition system, can be weak. Race engines (contrary to popular belief) require smaller gaps than most "stock" engines due to higher cylinder pressures and denser air/fuel mixtures. A good starting point is .035" then go up to ..040" and .045, noting each time how the engine idles, responds and pulls. Once you've gone bigger on the gaps, try going smaller to .032", .030" and .025" and again, note how the engine runs. Whatever the gap was when the engine ran it's best overall, is where you should gap your plugs at. TOP
Q: I have a high compression engine and I was told to run a colder sparkplug or I might overheat it, is this true?
A: A sparkplug doesn't make heat, therefore it can't heat up the engine. Sparkplugs can not and will not make an engine run hot (or cold). The fire in the cylinder heats up the plug, not the other way around. Heat range simply means how hot the plug itself will be. If the plug is too cold, it won't be able to burn off the oil and fuel deposits that collect on it and it will foul. If it is too hot, the electrode can't cool fast enough and it may start to melt away. On high compression engines, there is more cylinder heat so a colder plug is usually used. Sometimes the heat on race engines is so great, even cold plugs melt-off the electrodes. This is a common problem when running nitrous oxide. Some top fuel engines don't even run electrodes. The ground electrode is simply cut-off and removed because it will melt-off! The spark from the magnetos on those kind of race engines has no problem at all jumping from the center electrode to the edge of the plug. The bottom line is, you want to run the hottest plug you can without melting the electrode. This just assures a clean plug that yields a good spark. TOP
Q: My headers glow cherry red, what gives?
A: This is usually caused by two things. Either you are running real lean (not enough fuel) or your timing is too late (retarded). A lean cylinder makes a lot more heat and causes the headers to heat-up beyond their normal temperatures, thus causing them to glow. Late (retarded) timing will do the same thing because the fire in the cylinder is still burning when the exhaust valve is opening and the fire goes out into the headers, causing them to glow. TOP
Q: Where should I set the timing on my performance engine?
A: There really is no specific initial timing specs for any performance engine. You really have to time an engine of this sort solely by the total advance. Most naturally aspirated engines like a total advance of 34 to 36 degrees BTDC. Nitrous and supercharged engines run less than that, unless you plan on blowing the heads off the engine of blowing holes through your pistons. You need a timing light with a timing offset built-in to check and set the total advance. These are usually a few bucks more than the regular light but they do a lot more. Most street engines use either a vacuum advance and/or a mechanical advance (the weights inside the distributor) where true race engines are usually "locked-out" and have no advance in the distributor at all. They also have no vacuum advances mounted on them either in most cases. There are several types of timing that you need to know about. There's the initial timing, which is also known as "idle timing", which is what the timing is without the help of the mechanical weights inside the distributor, and without the vacuum advance working. Then there's the mechanical advance, which is the advance you get from the weights inside the distributor, and it's the initial timing AND the mechanical advance that gives you your TOTAL timing. For instance, say your distributor has 20 degrees of mechanical advance built into the weights inside, and you want a total of 36 degrees of total timing, you would need to set the initial timing at 16 degrees (16 degrees on the crank and 20 degrees from the mechanical weighths = 36 degrees of total timing) To find find and set the total advance, all you need to do is set the dial on your timing light to 36. Now rev your engine to about 3,500 RPM (to insure that the mechanical weights are fully activated) and watch your timing mark on the harmonic balancer. When it reads "0", (yet the light is set at 36), you have a total advance of 36 degrees. Make sure you do this with your vacuum advance NOT hooked-up. If you don't run a vacuum advance, then don't do anything, just leave everything as it is. If it reads higher or lower on the balancer, simply move your distributor until the timing mark is at "0". Your engine isn't really at "0" or Top Dead Center. The timing light is offsetting the light beam by 36 degrees (if its set at 36 degrees) so you should be reading "0" on the crank. The total advance will change if you replace your distributor or install an advance curve kit, so alway check it and KNOW where your timing is at, it's REAL important on more radical engines, especially on high compression / supercharged and/or nitrous engines! Now, if you do use a vacuum advance, (which is ONLY there for part throttle economy by the way...), hook it up AFTER you have set the total timing. Of course when you are driving down the highway at part throttle, the vacuum advance will pull anywhere from 10 to 15 degrees MORE advance (beyond your total timing), BUT under hard acceleration, the vacuum advance doesn't work anyway, so you're back on your total timing when you're on the throttle. Personally? I almost never use a vacuum advance. Remember this, a correctly timed engine produces the most horsepower. An engine with timing too late (retarded) will have a low idle vacuum, have slow throttle response, feel like a turd at low RPMs and will run hotter than normal. An engine with the timing too soon (advanced) will have a high and erratic vacuum signal, might have a snappy throttle response but not pull very well under a load, it will have pre-ignition (detonation) problems, sometimes called "pinging", which will certainly lead to either a blown head gasket and/or serious piston damage and it will idle rough, like it has a bigger cam than it actually does. Keep this in mind too, once you set your timing and you don't physically move the distributor, the timing will pretty much never go out. The first thing people do (who have no clue what the hell they're doing) when their engine starts running funny, is start twisting the distributor around and screwing with the timing. The timinmg will NOT affect any ONE particular cylinder. It can ONLY affect ALL of them at once, so if you have a back fire or a missfire or a dead cylinder, there is no need to start messing around with the timing. Again, if you don't move it, it'll stay set pretty much forever.TOP
Q: Can I run a high stall converter on the street?
A: Sure, as long as you have a good tranny cooler. One of the biggest bangs for the buck is a stall converter. I build "daily driven" street cars with anything from a 2,400 stall on up to a 3,500 stall and they are very streetable with no problems. There are a lot of people that will volunteer their opinion and "expertise" about stall converters by saying that you'll burn-up your tranny by running one on the street. Hey, large GM trucks use converters called GM-6 and GM-9 that stall out to 2,800+ RPM and that's on a severe duty vehicle that sees a hell of a lot more driving time than your car ever will! Yes, you'll be fine. Just be sure you use some sort of an external tranny cooler. TOP
Q: What does a high stall converter do?
I'll try to keep it short because it's an involved subject. Basically "stall" means when the torque converter "locks-up" under a load. With that, if you take a car with a 2,500RPM stall converter and you hold your foot on the brake hard, and hit the gas at the same time, (as if you were going to power brake), the "general" RPM in which the tires will break loose is at "about" 2,500RPM. If the converter was a 3,500RPM stall, then it would be at approximately that RPM in which it forces the tires to break loose. Keep in mind, if you put that same converter behind a nasty big block, in a car that has serious traction or is quite heavy, the torque of the engine will drive the stall speed up to a higher RPM, and an engine with less power will have the opposite effect and won't be able to stall the converter out as high. It's all relative to torque, vehicle weight and rear gearing. It isn't an exact science as far as an exact stall RPM goes.
Stock cars have anywhere from 1,000 to 1,400 RPM stalls from the factory. The reason a stall converter works is simple; an engine at 1,200 RPM is only making about 80 or so horsepower (on average), but at 2,500 RPM it could be making 150 to 200HP, and obviously trying to get a car moving using 150-200HP is going to be much better than one trying to launch at 80HP or so. Most performance engines don't make power until 3,000 or so RPM, hence why when you have a higher horsepower engine with a big cam, you need a higher stall speed so the engine is in it's "power band" when taking-off from the line, other wise it will fall on its face and be a turd off the line.
Some people believe that "stall" means the car won't start moving until the engine reaches that particular RPM, and that isn't even close to being true. We build race cars with 6,000+ RPM stall converters and when you put the car in gear and let it idle, it WILL roll along at 5 - 10 MPH, just like any other car will when put in gear and with the brake off. In fact, we usually cruise through the pits with the car simply in gear and idling, so if a 6,000RPM converter means that the car won't start moving UNTIL that RPM, then we'd have to have the engine wound-out to that RPM to put along through the pits at 10-15 MPH, and that simply isn't the case. Stall means that when the car is on the starting line, (with say a 4,500RPM stall converter), and the trans brake is on, (which locks the transmission in first and reverse at the same time), and you hit full throttle, the engine will wind-up to 4,500RPM with the car just sitting there, so when you slip your finger off the trans brake button and the tranny engages out of reverse, the car instantly launches at 4,500 RPM, and a race motor at 4,500RPM is pretty much at it's peak torque curve when leaving the line, hence the big wheelies you see on some drag cars or the incredibly low 60 Ft. times when traction is good. Race engines make no power at low RPM's, and are usually shy on torque, so the nastier the engine, the higher the stall speed needs to be (in general anyway). Again, cubic inches, torque, vehicle weight and gear ratio have a big factor in this.
A 6,000RPM converter behind a stock engine might not even get to 6,000RPM because the engine can't make enough torque (or power) to spool-up to that RPM because of the load of the converter. The car will start rolling at a much lower RPM and may never be able to reach 6,000RPM. This is also true for any converter from about 3,000RPM on up. Most mild race cars (9-10 second quarter mile times) use anywhere from 3,000 stalls to 4,500 stall speeds on average. Faster cars usually use even higher stall speeds, especially in smaller cubic inch engines that don't make the torque if big displacement engines. Also, the higher the stall speed, the more heat the converter will make, from hydraulic (fluid) friction inside the converter. A high stall converter can easily make enough heat to fry a transmission if you hold it on the line long enough at full RPM if the stall speed is above 3,500RPM or so, so a good tranny cooler is essential when running ANY type of high stall converter. TOP
Q: Is a 600cfm carb too big for a street engine?
A: That's a trick question. It depends on what kind of a carb it is. Is it a vacuum secondary or a double pumper? Is it a stock engine or a performance engine. Do you have a manual transmission or an automatic? These are all factors when choosing the right carb. Before I start, let me remind everyone of this. NASCAR engines have over 750 horsepower and spin between 8,000 and 9,000 RPM for 500 laps and they run a 390cfm carb! That's right, 390cfm! First of all, lets take a 600 double pumper, like Holley's #4776. It's a great little carb but as the throttle is pulled back, the primaries begin to open and a shot of fuel gets squirted down the throat from the primary accelerator pump. When the primaries get about halfway open, the secondaries begin to open (mechanically) along with another shot of fuel through the squirters, from the second accelerator pump, hence the name double pumper. This is all fine and dandy unless you've got an automatic transmission, a heavy car or high rear-end gears and you stab the throttle off the line. The engine will probably choke, cough and spit before it sluggishly starts to go. I call this "flushing the toilet". The key here is air speed or velocity, or rather lack of it! Picture this, take a shop vac and feel the suction at the end of the hose. Now make the hole smaller, the air being sucked in speeds up! This is an increase in velocity. When the throttle is stabbed, all 4 barrels opened-up at once and the air speed (a mixture of fuel and air) slows way down because the engine lost its vacuum. An engine can't go unless air (and fuel) are going into it! The faster the speed, the quicker the pick-up!
Now lets take another 600cfm carb, Holley's #1850. This is a vacuum secondary carb which has only one accelerator pump and secondaries that open via air speed passing through the carb. When the throttle is hammered, only the primaries open. This allows a faster air speed to feed the engine and no "toilet flushing". As the air passing through the primaries speeds-up, it passes over a small tube that acts like a siphon. This siphon is attached to the secondaries. They won't open-up until your engine says "Hey, I need more!". When they open, the air passing through the secondary side of the carb draws the fuel it needs through the rear jets, or in some cases metering plate. No bogging or dogging off the line! I see all too often cars coming into my shop with vacuum secondary carbs with a small screw stuck in the secondary linkage so when the gas pedal gets pushed, the secondaries are forced open, sort of like a double pumper. Don't do that! You'll just make a turd out of a good carb and defeat the purpose of vacuum secondaries.
Here's the deal on carbs. You can take a general V-8 engine and put a 650 double pumper carb (Holley #4777) on it. It will drive OK but probably be a turd out of the hole and get horrible gas mileage. You'd be much better off with a 750 vacuum secondary carb (Holley #3310) instead. Yes, CFM wise it's bigger, and technically it is, but in reality it works much better and the engine will rev faster, the car will launch and pull a lot harder and it'll get better gas mileage! If you have to "feather the throttle", your carb is probably too big. You don't want to be a dog off the line... always remember this... 80% of the race is the first 80 feet! TOP
Q: My engine idles real high and rough and when I try do drop the idle down, it dies. What gives?
A: This is usually caused by two things. The vacuum advance being hooked-up to the wrong port on the carb or a big vacuum leak somewhere. A vacuum advance always gets hooked-up to "ported vacuum" which is a port somewhere on the carb above the base plate. On Holley's, it's on the passenger side, halfway up the side of the carb on the metering block. DO NOT hook-up a vacuum advance to manifold vacuum. If you can put your finger on the vacuum port and you feel suction, don't use that port!
The other thing that could cause this is a vacuum leak. You can usually find vacuum leaks by spraying carb cleaner around the outside of the carb and around the intake manifold. If the idle goes up when you spray it, there's your leak. Another way to check for internal leaks, like internal carb leaks or leaks under the intake manifold (in the valley) is to hold your hand over the top of the carb, blocking-off most of the incoming air. The engine should immediately die. If the idle goes up at all, you've got an internal vacuum leak somewhere. TOP
Q: When do I need an after market ignition system?
A: Probably never! All of the after market ignition companies claim that you'll get more horsepower by using their ignition system. I hate to burst bubbles but the fact is, numerous independent dyno studies have shown no gain what so ever! Don't get me wrong. I like a lot of after market ignitions and my own blown and nitroused car uses one as well. The object of the game is to ignite the cylinder. Once the cylinder is lit, it's lit. It either fires or it doesn't. I can't tell you how many racers and street buffs I know that have small fortunes invested in their ignition systems when GM's stock HEI system would have done the same job... if not better! Ford has the worst stock (electronic) ignitions systems. Their factory modules stink. They have the least amount of dwell time and the most expensive price. Chrylser has a great module that will saturate the heck out of the coil, causing a big spark. A neat trick is to use a Chrysler module on a Ford engine. It really wakes-up the coil. I can't tell you how many people say that you can't run an HEI distributor an a high performance engine because they "sputter" after 6,000 RPM. Say that to our Super Gasser that runs 9.90's all day long and goes through the lights at almost 8,000 RPM without a glitch. I took that MSD 7AL2 box, billet distributor and funky coil and trashed 'em because they were doing strange things and dropping cylinders when the car came-off the trans brake at 6,500RPM. I've had people come-up and say "hey, you can't run an HEI distributor at those RPM's", as they watch the car go down the track without a glitch! You can't check those elaborate ignition systems and when they need fixing, you've either got to send them back and wait 2 weeks or spend a fortune on a new one. I've built street cars that run 11's and 12's using HEI ignitions and stock Ford distributors using Chrysler modules, and when you hear one of those engines wound-up to 8,000 RPM without a sputter you'll be a believer! TOP
Q: What's the right way to break-in an engine?
A: There are a few steps that must be taken when starting a brand new engine. By far, the most critical and important thing is breaking-in the cam. Upon initial start-up, the engine MUST be run for 15 to 20 minutes at about 1,500 to 2,000 RPM. This seats the lifters to the cam and vise verse. If you are using double or triple valve springs, you MUST remove the inner springs and break-in the cam using only the outer springs or you will surely end-up with a flat cam! Roller cams do not need to be broken-in, but ALL flat tappet cams must. Do NOT break-in your cam with non-detergent oil! This is old school and these days, you can't even get good non-detergent engine oil. Use a good, high grade oil like Valvoline 20w-50 or straight 30 wt., Castrol 20w-40 or Kendall. Once the cam has been broken-in, you can re-install the inner springs (if you're running them) and do all of the usual things like set the timing, adjust the carb and idle, etc. It's always a good idea to have a garden hose handy when breaking-in cams because there's usually a large air pocket in the cooling system and running an engine at 2,000 RPM for 20 minutes can cause it to heat up. Just spray the radiator down while the engine is running and it will help keep things cool.
The second part of breaking-in an engine isn't really that important. I don't believe in driving under 60 MPH or keeping the revs below 4,000 RPM for the first 500 miles. What I usually recommend is that after the cam is broken-in, go drive up a hill a couple of times, slowing and accelerating as you go up. This builds-up heat and puts a variable load on the engine which helps seat the rings. Pussy-footin' a new engine can cause the cylinders to glaze and the rings may never seat properly. As far as revving the engine? Go for it! You don't think we build race engines and drive them for 500 or 1,000 miles before we rev them up do you? Heck no! As soon as the cam is broken-in, it's at the red line, going down the track! What you want to avoid on street engines besides pussy-footin' around is getting on the highway and going the same speed for extended periods of time. It doesn't matter if it's 40MPH or 70MPH, just don't hold it there. Instead, vary your speed, pass a few people and then slow down for a bit, and then speed back up. This varies the engine load and helps things seat-in better. Be sure to change your oil and filter after the first hundred or so miles because when an engine breaks-in, little tiny, fine particles of metal are wearing-off inside and floating around in the oil. This is all pert of the break-in process and is totally normal. TOP
Q: Are 4 bolt main blocks that much stronger than 2 bolt main blocks?
A: Lets start with what a 2 and 4 bolt main is anyway. What holds your crankshaft in are main caps. These are what the crank bearings sit in and most engines have 5 caps. A 2 bolt cap is fastened to the block by 2 bolts and a 4 bolt cap has 4 bolts (2 on each side). Main caps are the only thing keeping your crank from falling out the bottom of your engine. When you increase the load on the crank, you inherently increase the load on the main caps. Any time you increase horsepower, torque and cylinder pressure, you increase crankshaft load. It would take quite a bit more stress to rip-out 4 bolts than it would just 2, so that's why the 4 bolt mains are stronger than the 2 boilt mains. This is the theory behind it anyway. I have to say though... I have never seen a crank get "blown-out" of an engine, be it a 2 bolt or a 4 bolt main engine. I have seen engines "blow-up", leaving pieces of crank and engine block all over the track but it is usually due to metal fatigue and failure somewhere else and not the main caps blowing-off. I have also seen 2 bolt main engines in low budget race cars running 9 and 10 second et's that last season after season. The more compression / cylinder pressure an engine has, the more the crank is trying to be pushed out the bottom of the engine, especially when a blower or nitrous is used. A way to make a 2 bolt main block even stronger than a 4 bolt block is to use a "main support". This is a brace that bolts across all 5 main caps, thus tying them all together and sort of creating a 10 bolt main engine. The theory behind this is simple, if one main cap tries to come-off, it has to take all of the others with it at the same time. It dispurses the load across all of the main caps evenly. If you are going to be building a street engine that has 11:1 compression or less, then a 2 bolt main block would be just fine. Anything higher than 11:1 or so, or if you are going to run nitrous or a blower, then I would recommend a 4 bolt block or a 2 bolt block with a main support just to be safe. Think of it like this, ALL of the early Vette 327's with 365 and 375HP were 2 bolt main blocks. There was no such thing as a 4 bolt main 327. How about the infamous 68 "MO" 302 Z/28's which were famous for 8,000RPM shifts in stock trim! They came stock with 11.25:1 compression and were indeed high winders that saw race track use quite often, and they were also 2 boly main blocks! How about the famous Shelby GT-350's? ALL of those were 2 bolt main "K code" 289's as well, which also saw 6,000-7,000RPM use VERY often. Now ask yourself, how many Vette's, early Z/28's or Shelby's have you ever seen on the side of the road with the cranks blown out? I'm not saying you should go out and build a race engine using a 2 bolt main block, but I want you to understand "reality". If you're building a sub 425-450HP engine, a 2 bolt main block will be just fine if it is set-up well, especially if it's a short stroke engine. Bigger stroker's are another story... if you are wanting a 383 stroker, I would suggest using a 4 bolt main block simply because of the longer stroke. TOP
Q: Should I have my engine balanced and blueprinted?
A: This one is a 2 part question. First the balancing. There are 2 ways to balancing an engine. The first is weight matching. This is done by weighing all of your pistons on a balancing scale. Once you find the lightest one, you then remove a little metal from the others (in a place that won't weaken the part) until they all weigh the same. Parts are usually measured within a quarter gram. This procedure is then done to the connecting rods. Once they are all done, then the rod is weighed on a balancing fulcrum which determines how heavy the rod is at either end. If one rod is a little heavier on the big end (where the bearing goes) than another, a little weight is removed from the heavier one to balance them out. After that is all said and done, the next step is dynamic balancing. This is when the rotating assembly (crank, rods, pistons) are put on a machine (sort of like a tire spin balancer) and the counter weights of the crank are weighed against the piston/rod combo. If a light weight set of rods and pistons are used, then usually a little material needs to be taken out of the crankshaft to even it out. If a heavier set of rods and pistons are used, then weight usually needs to be added to the crank weights. This is done by drilling holes into the crank counter weights and pressing in cylinder shaped slugs of heavy metal known as Mallory metal to increase the weight. Street engines do not necessarily need balancing. Except for a couple of rare occasions, almost no factory engine ever came fully balanced, even most "performance" engines weren't balanced. Balancing helps an engine run smoother with less vibration which creates less havoc on main bearings and helps things last longer.
Blueprinting is an interesting term. Almost no engine is blueprinted. Blueprinting means following a set of specs to the "T". Most serious race engines such as Indy, NASCAR, Formula 1, etc. are blueprinted engines. Most teams have several back-up engines and every single one is identical to the other in every way. Blueprinting can also mean (loosely) building an engine by following a set of factory specs. The only problem with this is that there are given areas of tolerances, not just one specific number. For instance: A blueprinted set of engines will have EXACTLY the same crank clearances. They will have exactly the same amount of piston to cylinder wall clearances as well as ring gap clearances, cam timing, head port and chamber volumes and so on where as a factor spec book will have "tolerances" that vary slightly. A blueprinted engine will call for .00275" main bearing clearance where as a the factory specs say anything from .0015 to .0030" is "within spec". There is no "within spec for blueprinted engines! It either is or it isn't and there's no in between. If you blueprinted two engines by the factory specs, there will always be variances between rod and main bearing clearances, piston clearances, deck height differences, valve spring pressure differences as well as Intake and exhaust port and chamber volume differences. It takes pain staking hours to truly blueprint an engine and for what? A ton of money and really nothing gained unless you are running the exact same car at the exact same track and you need to go the exact same speed as you were with the last engine. TOP
Q: Are forged cranks stronger than cast cranks?
A: Yes they are. In the days gone by, forged steel cranks were the way to go and they still are if you're building an all out racing engine. Some factory engines came with forged cranks. The stock small journal 327's and 283 ALL had forged steel cranks. Some of the early high performance 350's came with forged cranks as well. There are many types of steel used for making cranks though, be them cast or forged and some cast cranks these days are just as strong (if not stronger) than older forged ones. There used to be just cast iron, nodular iron and forged steel available. Now, for the most part, there's cast steel, 4130 and 5140 forged steel and super strong 4340 forged steel available. The new cast steel cranks are very cost effective and plenty strong for even most mild racing engines. I have seen forged cranks break in half for no visible reason at all, yet I have seen cast cranks survive season after season in mild race cars. I recommend using forged cranks in serious street and race engines, and stroker's, especially if you are using nitrous or a supercharger. Stay away from the Chinese and Taiwan made junk. I am not a fan of the Mexican made forged cranks either. Those come is all of the late model factory crate engines. Comparing those types of cranks to a high quality crank is like comparing a Chinese made 6 dollar set of sockets to a high quality / high strength set of 80 dollar Snap-On or Mac Tools sockets. There's no comparison, especially when you find-out the cheap, Chinese sockets break the first time you try to use them. Well, "steel" cranks aren't any different except for the fact that when you go "cheap" in an engine, you are asking for a MAJOR failure that takes everything else along with it. Is that worth it? No way! That's why we don't use that kind of crap in our engines, but you sure see that crap in all of the "bargain priced" magazine ad engines out there. You certainly don't need a $4,000 profiled, ultra light, billet steel crank like you'd find in a Nascar engine, or even a $1,500 high quality forged steel crank in well built street / strip engine, but you also certainly don't want to run a $189.00 piece of crap crank in an engine that is going to make some serious power. Just remember, you get what you pay for. TOP
Q: How come I get oil leaks at the corners of my intake manifold?
A: Most rebuilt engines have been machined in one way or another. Two of these places are the block's deck surface and the other is the head surface. Every time material is removed from these two spots by "decking the block" or "surfacing the heads", the intake manifold sits higher on the block simply because you have "lowered" the heads by machining the surfaces. When you try to stuff those rubber or cork end seals underneath your intake manifold, it causes the manifold to ride even higher and you either need real thick intake manifold gaskets or you need to have your intake manifold end surfaces machined down a bit. The easiest way is to throw out those end seals and just use a bead of silicone. The oil in the lifter valley is just splash and not under pressure. Another big problem you run into when trying to use those end seals are vacuum leaks underneath the intake manifold. It's best to just not use those seals in the first place and go with the silicone instead. TOP
Q: Do "202" heads make more power?
A: Yes and no. "202" refers to the intake valve diameter of 2.02". Fords and Chevys do not have an intake problem... they have an exhaust problem. If you've got a set of stock cast iron heads and had them fitted with 2.02" valves and think you're going to get more horsepower, you're just kidding yourself unless you did some more machine work and "un-shrouded", or relieved the valve area inside the combustion chamber PLUS added larger exhaust valves. You can actually lose flow by installing valves that are too big for the combustion chamber unless they are un-shrouded. It's pretty simple, what goes in, MUST come out! On hot street engines, you'd be better off leaving the 1.94" intake valves alone and opting for a set of 1.60" or 1.65" exhaust valves. Don't believe me? Look at 99.9% of all dual profile cams. Almost all of them have more lift and duration on the exhaust side than they do on the intake side. Gee, I wonder why? TOP
Q: Can I put Chevy valves in my small block Ford heads?
A: Yes. This is a pretty common swap for early 289-351W heads. Both Ford and Chevy heads use 11/32" valve stems and are very close in length. The 1.94" and 1.50" Chevy valves fit nicely into the athsmatic Ford heads IF they are un-shrouded. A little pocket porting and gasket matching goes a long way with this swap! TOP
Q: Why shouldn't I just go buy a "crate motor"?
A: That's fine but remember this; The new small block Chevy is made in Mexico and is about 60 lbs. lighter than the older castings which means there is 60 pounds of reinforcement missing as well. They come with things like plastic timing covers and Brazilian made pistons. No thanks, that kind of stuff won't hold-up to the kind of abuse I'm used to putting my motors through. If you're going for performance, those 210 HP, 330 HP and even the 355 and 385HP crate motors just aren't designed to withstand the abuse serious racing or "playing hard" on the street that some guy's put their motors through. The crate motor is for the kind of guy that want a basic engine, and if that's what you want, fine.. what are you doing on this web site? Bad-Ass engines are for the hard core hot rodder / street racer that needs something with more power and strength than a regular crate motor can offer. TOP
Q: Is it better to de-stroke or increase stroke on an engine for more power?
There is no single correct answer to this question and we need to determine what "power" really means. The rule here is "leverage". Think of it like this. Picture your crank being like a wrench. If you are trying to loosen a bolt and you have a short wrench, it's going to be pretty hard to break it loose because you don't have enough leverage, but once it is loose, you can turn that short wrench pretty fast and remove that bolt quickly. Now, if you get a longer wrench, you'll be able to break that bolt loose pretty easily but once it's loose, it's pretty hard to turn that long wrench very fast. So it's kind of a catch 22 situation. Cranks work exactly like that. A longer stroke makes for greater leverage which equals more torque. A long stroke acts like long wrenches, making it easier for the engine to pull a heavy load but in return, it can't spin very fast because of the reciprocating mass. A short stroke makes an engine rev fast because of less reciprocating mass but it's like that short wrench, it's makes it tough to pull heavy loads or make much torque being that there's less leverage. Let's apply this to specific engines and determine if increasing or decreasing stroke is better or even worth the effort in the first place. If we use a Chevy 350 (3.48" stroke) and want to de-stroke it by 1/4" (3.25" stroke) you end up with a 327. By de-stroking a half inch (3.00" stroke) you end up with a 302 made famous by the early Z/28's. A very high revving small block that made pretty good power at high RPM's but had almost no low-end power at all. By up-stroking the 350 engine by 1/4" (3.75") we end up with a 383, which is notorious for making good torque at low RPM's and being able to rev pretty well but not as high as the shorter stroked engines. Stroking Ford's is another story. You can up-stroke a 302 and end-up with a 347 or even a 357 cubic inch engine, but that's a pretty expensive way to go when compared to the 351W which is way stronger than a 302 ever thought of being and is only about 1" wider overall. If you add stroke to a 351W, you can end-up with a 396, a 408, and a 427 in a small, light package for the same money it would take to build a smaller and weaker 347. There are many other factors involved in stroking such as faster piston speeds, increased rod angles and so on, that would take page after page to go into. . If you have a heavy car and/or tall gears, you're going to need a lot of leverage to make that car move. If you have a light car and/or short gears, you can utilize less leverage and spin it faster. If you can just remember the basics of "leverage" you'll be able to understand it all a little better and choose which way is best for your application. TOP
Q: Are high volume oil pumps OK to run on the street?
We get asked this one from time to time. It depends on the engine. A Chevy engine can use a high volume oil pump just fine where most small block and even some big block Ford's have trouble running one. Why? Some people say that a high volume oil pump can pump all of the oil to the top of the motor and basically empty out the oil pan before it can all drain back again. Yeah right, no way! A high volume oil pump only pumps about 20% to 30% more oil. So that would mean that your stock pump is only 20 or 30% away from sucking your oil pan dry? I don't think so. The real reason is this: Chevy's use a larger distributor gear than a Ford, in fact, it's about twice the size. The distributor gear is what takes the load of spinning the oil pump. Ford gears tend to get eaten-up because they just can't take the load of a high volume oil pump. Once you eat-up a distributor gear, it is pretty much disaster for the cam gear as well plus all of that metal going through the engine doesn't help things either. We tend to use stock oil pumps on Ford's and high volume pumps on Chevy's, as far as stock and performance street engines go. On race Ford engines, we run high volume pumps and just keep a close eye on the distributor gear for premature wear. TOP
Q: How much is a "turn key" engine?
This is a pretty open question. We sell most of our engines as "long blocks" which are complete engines with the heads and everything all put together except the "tin" such as valve covers, oil pan, water pump, fuel pump, etc., unless otherwise stated in the description. We list every engine and what it comes with on our web site pretty clearly. If it says it comes complete with oil pan, intake manifold, etc. then it those are included in the price listed and if it doesn't list those items, then they ain't included. Keep in mind, we build countless engines and engine combinations. What's listed on our web site is only a tiny fraction of what we build. If you want a "turn key" engine, complete with everything from carb to pan, water pump to flywheel, we can do that for you. As far as price goes, that's where the "open question" comes in. We don't list engines like that on our site because there's just too many variables that can sway the price one way or the other. If we list a complete "turn key" engine, are we supposed to list a price for a $249 Holley carb on it or a $500+ custom built Holley carb? Should we give you a price on a polished aluminum / high flow water pump or a stock, off the shelf rebuilt water pump. There's at least $100 difference between the two. How about the valve covers? Are we talking $400 fabricated aluminum covers or $20 chrome steel covers? What about something as simple as a harmonic balancer? Do we list a price for a stock, $79 balancer or a $400 SFI approved after market balancer? Now, you still have the flywheel, the timing cover, oil pan, the fuel pump, the ignition... hell, those items alone can sway the price more than $1,000 one way or the other depending on which parts are used. So the question is, do we list a "turn key" engine with all of the good stuff that costs a lot or with cheaper stuff that doesn't cost a lot and what about the up-teen million other variations in between? If you're a serious buyer, we can put a price together for you with the parts you want but we don't already have prices made-up. TOP
Q: How do I order a BAD-ASS engine?
It's pretty simple. You e-mail or call us and make an appointment to come in. Then we'll sit down and go over everything you want and tailor the engine to your exact needs. EVERYTHING gets written out on a shop work order in great detail as to exactly what you will be getting with an exact price and you get a copy right then and there. If you're out of our immediate area, what we do is similar only after we have filled-out a highly detailed work order, we'll send you a copy so you can review it. When your are ready, you simply make out your check with the work order number on it and send it to us. This assures you of exactly what you will be getting. We require at least a 60% deposit before we will start building any engine and the balance upon "completion". That means when the engine is finished, not when you feel like coming-in to pick it up. For out of area orders, we require the whole amount in advance. PLEASE, if you are not serious and ready to make a purchase, don't waste our time by having us make out a work order for you! It takes quite a bit of valuable time to sit down and look-up all of the parts and prices needed to put a work order together and time is not something that comes easy around here. If you want prices, go to our PRICES page. That's what it's there for. TOP
Q: How do you crate and ship your engines?
If you need an engine shipped, we will mount it on a standard pallet and seal it up real well with industrial plastic so no rain, dirt or dust can get in. It looks like a cocoon when we are finished with it! Truck freight is NOT included in the price of the engines. Although we will "help" each customer with the shipping part, we do leave that task up to the customer to handle, which is really easy to do by clicking HERE. We ship all of our engines across the nation and around the world through www.FreightQuote.com and they are by far the best at both service and price. When the engine leaves our shop, we take digital pictures of it as it left to show the exact condition of it at that time. If in the very unlikely event that something happens to it in the trucking process, (which is extremely rare) you must take it up with the trucking company though, and not us! If they break or damage it, then they can pay for it. We do our very vest to make the shipping process as easy as possible, and really, it IS easy and fast. They have all of our infomation and they know exactly what to do to help you out. We do our best to make sure everything runs smooth for you and that you get your nice, new power plant in excellent condition.TOP
Q: Do I need to trade-in my old engine core?
Most of the engines listed on our web site have the word "outright" listed by the price. "Outright" means just that... that there is no core needed for that engine. Some engines do require a core and if it doesn't say "outright" next to the price, then we need your old engine or a core charge will be charged. For more information on cores, click HERE. TOP
Q: What do your engines come with?
We get this one a lot for some reason and we just can't figure out why when everything is spelled out in plain English exactly what comes with that particular engine in the description. We even get questions like "do your engines come assembled?". Hello? Of course they come assembled! Here's the deal, the engines listed on this web site DO NOT EXIST in reality! They are ONLY for comparison reasons so you can see what you get for how much $$ and that's it. When you order an engine, we build it to YOUR specific needs. We can add, subtract or change anything you want. If we pre-built engines and had them laying around, they would be nothing more than crate engines... we don't build boring, generic crate engines! If you don't see something listed in the description, then that engine doesn't come with it for the price listed.. it's pretty simple. If you want something that isn't listed in the description, we can surely add it to the engine and adjust the price accordingly when we build it for you, that's why we leave every option open, so you get an engine that is just right for you and your car. There is no one perfect engine or horsepower rating or we would surely be building it! If you want more with an engine than is listed in the description, we can do that, no problem but see the title "How much is a turn key engine" here in the tech tips section before you go any further. TOP
Q: Why does my engine still try to run when I shut it off?
This is a common problem that can be caused by a couple of things. Some people call this "dieseling" or "run-on". What is happening is, when you shut the ignition off, something, somehow is causing a couple of the cylinders to keep igniting, which in turn keeps the engine running, although "sputtering" pretty badly. This can be caused by excessive carbon build-up in the combustion chambers or on the piston tops which when hot, acts like little glow plugs. This is common on engines that run way too rich or have oil burning problems. Dieseling is a common problem with high compression / high performance engines, especially in warm weather or when the engine is hot. In this case, it is usually caused by running "cheap" gas with inadequate octane. It can usually be remedied by switching to a higher octane fuel.
In milder street engines, another big cause for engine run-on is having the idle set too high, or the carb misadjusted which requires the idle speed screw to be screwed-in too far. When the idle speed screw is screwed-in too far, it opens the throttle plates too wide and when you shut the engine off, the heat built-up inside the combustion chambers is enough to light a few of the cylinders at random and keep the engine spinning. Again, this is especially true with fuel that isn't high enough in octane. The more the octane the less volitile the fuel. Even though the key is off, the engine won't stop sputtering because the throttle plates are opened up enough to still pass fuel and air. This is why modern cars have idle stop solenoids and electronic injectors that shut the fuel and air off, (as well as the ignition), when the key is turned off. Carburetors aren't electric, so even when you shut off the ignition, the inertia of the engine is still moving, (and sucking-in air), and as long as it is still rotating, the fuel and air is still flowing and feeding the cylinders. There is a true way to remedy this problem which involves the vacuum advance and the ignition timing. Even though the timing has nothing to do with engine run-on, (because they key is turned off and "ignition timing" is no longer in play), there IS a way to fix this problem once and for all on just about any engine, but it would take me a while to explain that and I already give enough free info on here as it is. If you want to learn about the really cool stuff like that, you're going to have to buy my Performance Tuning DVD set and learn how this stuff works :-) If you find that you can't tune out the problem yourself, then there is a quick solution. It won't fix the problem but it stops the symptoms. In cars equipped with automatic transmissions you can simply shut the engine off while still in "Drive" and the load from the tranny will cause the engine to shut right off. Manual transmission cars can be shut off while in gear (with the clutch pedal down) letting the pedal back up slowly when the key is turned off to load down the engine.TOPQ: What's the difference between a BAD-ASS engine and one from my local discount auto parts supplier?
We run into this one all of the time. People call, asking for a price on a rebuilt "stock" engine and compare our price to the $699 price they see advertised at their local discount auto parts store. There's a BIG difference between our engines and those so-called "rebuilt" engines. Our engines always get new parts such as pistons, cams, lifters, oil pumps, oil pump drive shafts, timing gears and chains, bearings, push rods, rocker arms, valves, valve springs, and so on. Those bargain prices engines get rebuilt by some kid making $6.00 an hour that has the choice to re-use certain parts that "look OK" and are thought to be reusable, plus, they do "valve jobs" instead of replacing them with new ones. If you go to your local parts store and read the whole advertisement, it will say things like, "valve job", re-ground cam, and there is always an "*" symbol next to all of the new parts listed and when you look at the bottom of the sign it says in real fine print, "new parts replaced as needed". HELLO? That means that if they thought the pistons "looked OK", they'll re-use them or if the old rocker arms, timing sets, push rods and so on "looked OK", they got re-used! Is that what you call a rebuilt engine and is that what you want to put in your car? You get what you pay for. It's no skin off their nose to hand you another engine when that $699 piece of crap fails, but it's you that has to rip-out the old one and put back yet another piece of crap that may go bad as well, and if you aren't doing your own work, then it's going to cost you money every time the engine has to come back out and go back in. We have a zero return rate here. Since 1978, when we first started building engines, we have had no engines returned for warranty or for dis-satisfaction! Does that tell you anything? TOP
Q: My engine backfires sometimes, could it be the timing?
Back firing is usually caused by a spark plug "sparking" when either the intake valve is open or when the exhaust valve is open. The engine timing doesn't really have much to do with the whole thing. When you turn the distributor, you are affecting the timing for the whole engine, not just one or two cylinders. When a back fire occur, it is just one or two cylinders, so the overall timing usually isn't the culprit. Once the timing has been set, if you don't move the distributor or make any changes to the internals of the distributor, then the timing should never go out unless you physically move the distributor again. Backfiring through the carb (spitting) can occur in the mornings when a carb's air/fuel mixture is too lean. This goes away once the engine warms-up. It can also be caused by a bad ignition system, such as plug wires cross firing which sends a spark to a cylinder that has the intake valve open. When that plug sparks out of turn, it lights the fuel in the cylinder and the pressure has to go somewhere... if the intake valve is open, it goes right back up through the intake manifold and out the carb with a "spit" and sometimes even a flame. When the air/fuel mixture is too rich and there is unburned fuel in the exhaust system and cross fire occurs when the exhaust valve is open, it will ignite the rich / unburned mixture in the exhaust manifold and tail pipes, which results in a big bang out the tail pipes. Back firing can also be cause by a cracked distributor cap, or one that has carbon tracking inside which causes cross firing between the terminals inside, which in turn, sends spark to a spark plug that isn't ready for it yet. So if you have an occasional backfire, don't start messing with the overall timing, start looking for a problem somewhere else down the line. TOP
Q: What's considered a "streetable" engine?
What we consider "streetable" is an engine that runs on pump gas that can actually drive around, cruise and even go on trips. The thing you need to remember is that ANY modified engine is going to have a "quirk" or two. Quirks can be any number of things and are directly related to how radical the engine is. A 350HP 350 is a fairly stock engine to us and would have very few quirks, if any at all. A 450HP (or more) 350 however, will have a few quirks and they will vary depending on the car and driver. Here's a few examples; A radical engine like that will idle much differently than other cars and will have less idle vacuum. This means that if you have an automatic transmission, you will probably have a low idle when sitting at a stop sign in gear unless you installed a higher stall torque converter or you blip the throttle here and there to remedy the problem. Low idle vacuum also means that you may have to press on the brake pedal with a little more force than normal if you have power brakes. These are no big deal, just quirks. Manual transmission cars don't have an "in gear" idling problem but some radical engines may idle differently from stop sign to stop sign, just depending on engine temperature, idle mixture, outside air temperature and so on. That too is no big deal, just a quirk that you deal with. Other quirks may be dieseling on a hot day. This is can be cause by sevaral things such as the carb being too rich which promotes carbon build-up in the combustion chambers that glows when it gets hot and acts like glow plugs so when you turn-off the ignition switch, the glowing carbon keeps a couple of the cylinders firing. This is especially prone in high compression engines. It can also be cause by the idle being set too high or the timing too far advanced. This is a simple problem to deal with and can be easily fixed once you know what's causing it. We do have many customer's that have all-out racing engines in their cars, running on alcohol or race fuel. Hell, there are a couple of guy's with blown alky engines running around on the street in full-on tube chassis race cars with headlights and a license plate! That to us, isn't what we mean by "streetable", even though these guy's actually drive on the street. The more horsepower you go with, the more you'll need to modify your car to get the most out of your engine. Things like lower rear-end gears are sometimes a must with high HP engines, or it might be a dog off the line, regardless of how much HP it's making. Hey, if gears weren't that important, you wouldn't see race cars running 4.88"s and 5.13's. They'd be running 3.00 gears instead if they could, but they can't or their engines, (even though they make lots of power) wouldn't pull hard enough. Other modifications that may be needed could be the exhaust system, the cooling system (horsepower makes heat) and so on. These are simply upgrades to compliment a high horsepower power plant and when you have a matched combination all working together, it's very streetable and very fast! TOP
Why do people sometimes rev their engine up and then shut the key off while it's still revved-up before they park? We see people doing this all of the time, especially with hot rods and such. Where this originated from was the old Ford Model T's. Those engines had to be hand cranked, but if you knew the trick, you could sometimes start the engine without having to get out and crank-'er up. Old cars like that had the throttle and ignition timing on the steering column. If you revved up your engine and shut the ignition off while it was still spinning, you essentially flooded the cylinders with raw, unburned fuel (being that the spark is no longer lighting the cylinders and the engine is still spinning). When you got back in your car, you could turn-on the ignition and move the timing lever so that one of the cylinders would actually get spark and ignite. When that cylinder ignited, it would cause the engine to rotate and start running all by itself. Pretty cool huh? Well, for some reason, hot rodders find a need to do this same thing except we don't have to get out and hand crank our engines any more. Remember I just said that when you do this, it floods the cylinders with raw, unburned fuel? Yeah, what happens to oil when you pour gas on it? It dissolves it. I mean, if you dip a piece of metal in oil and then dip it in gasoline, the oil comes-off. So what it the ONLY thing protecting your cylinder walls from being scuffed by the pistons? The thin layer of oil on them. When you douse the inside of the engine with raw fuel, you wash-off that protective layer of oil and cause cylinder scuffing plus you lose your ring seal. This is a common occurrence with engines that run too rich and get what is called "cylinder wash-down". This is caused by too much fuel in the cylinder that can't all get burned, so what is left over is a wet mixture of raw fuel that literally "washes" the oil right off the cylinder walls which in turn causes the rings to lose their seal which in turn results in a major drop in compression, plus the scuffing going-on from the piston not having a protective layer of oil between it and the cylinder wall. How can you tell if your engine is running way too rich? There are two simple ways. The first and easiest id to simply pull out your oil dip stick and smell the oil on it. If it smells like gas, then raw gas is getting past your rings and into the oil. The second way is to pull a spark plug or two and see what they look like. A plug fouling from fuel will have a fine, black suitty powder on it. If you are really running rich, the plug may be wet and smell like raw gas. Wet, gooey, cakey deposits on a plug are usually from oil, not fuel. TOP
Q: Are all of your engines started and run on a dyno before you ship them?
No, only if we arranged to do this before hand and it isn't a very cheap thing to do. Some engine companies (we won't name any names here) advertise in magazines boasting about dyno running all of their engines before they sell them. If you've ever worked with a dyno before, you'd know that it isn't just something that happens in 15 or 20 minutes. It takes at least a day and sometimes even 2 days or more just to start and run an engine on one. If it is an all-out racing engine, it may be on the dyno for a week or so, depending on how much trial and error you want to put into testing it and even changing different parts such as cams or alter the cam timing, rockers, heads, carbs or whatever you may be trying at the time. Keep this in mind. A dyno is a very expensive piece of equipment (about $25 grand), once an engine is built it will need to be mounted on the dyno, have the flywheel hooked-up to the water brake, then you have to install the spark plugs, the distributor, install the plug wires, mount a water pump and fuel pump, plumb-in the carburetor, install a fuel filter, install the oil filter and add oil. Then there's the belts and pulleys that need to be mounted as well. After that, the engine needs to be started and run for about 20 to 30 minutes to break-in the cam. Then the timing must be set as well as the carb adjustments. Then it's a good idea to let the engine cool down for a while and in the mean time... the break-in oil gets dumped along with the first oil filter and more oil goes back in along with another filter and if it has a flat tappet cam, the heads will now need to be torn down so the inner valve springs can be reinstalled, being that you can NOT break-in a flat tappet cam with double or triple valve springs. Then the engine has to be run again for at least another 10 to 15 minutes before any hard pulls can be done to ensure proper running temperatures and oil temps, exhaust gas temps and so on. Then you can make a pull and see what you get. After that, you can play with the timing a bit, play with the carb jetting or swap that carb for an entirely different one, try a carb spacer or whatever you think needs to be done and do it all over again. Like I said, it takes a lot of time to do it right and no one works for free or pays $25,000 for a dyno to GIVE away free dyno pulls. As you can now see, it is pretty involved, quite time consuming and there are a lot of little extra parts that need to be purchased and used to make it all happen. Is that stuff supposed to be free or included in an already great price on your engine? Hardly. So the next time you see a magazine add boasting about a so-called "great engine" at a bargain price that says each one has been run and dyno tested, think about what all has to go into it and where do they work all of that extra time and parts into the price... by having $6.00 an hour high school kids building and assembling their engines is how, because there is NO WAY a professional engine builder is going to do it for free or at almost nothing per hour... and is that something you want to have in YOUR car? I doubt it... TOP
Q: I heard that forged pistons knock
That's un-true unless you are running some seriously wide clearances. Less expensive forged pistons and pistons from yester-year used to have wide tolerances due to the higher expansion rate of the forging compared to a cast piston. For instance; a cast stock piston only needs about .001" clearance betwe