There are several ways of making free horsepower on most older cars. When an alternator "energizes" and begins charging, it loads down and can suck up about 10 to 12 horsepower. Don't believe me? Fine. Just listen to your engine lug down 50 to 100 RPM when you hook-up some jumper cables to jump start a friend with a dead battery. That my friend's is the alternator lugging the engine down under a load. Justhow much power do you think it takes to force an engine to drop in idle 100 RPM? If you are racing at night with your headlights on or your battery is a little low... then your engine is being put through the same "load" as you're racing down the track. You can gain this HP back by simply installing a switch in the "field" wire to shut it off. The field supplies the alternator with electricity which energizes it, or basically, "turns it on". Alternators need electricity to work, unlike old generators, so if you don't allow this field wire to energize the alternator then you have gained a few more ponies. To do this though, you MUST turn the engine off first and make sure the key is off when the alternator kill switch is turned off, otherwise the alternator will NOT "de-energize" if the engne is already running. Once the engine's running and you want to re-energize the alternator, simply flip the switch while you're driving and it instantly turns-on. Now, a BIG down side to this is if you have a high energy ignition system, ESPECIALLY something like an MSD box! Those boxes need full power to function properly. If you try this alternator trick when you have anything other than an old points type ignition system you'll end up LOSING power because the poor ignition system isn't going to like it. The battery alone is barely enough to run an MSD sustem. You REALLY need the additional current and voltage from the charging system if you are running one of those. I said this was free horsepower, I didn't say it woud be a great idea for all vehicles :-)
Indexing your spark plugs is another way of gaining you a few extra horsepower. The object is to get the gap of the plug facing the intake valve, or at least facing the open area of the cylinder. If a spark plug's ground strap is facing the intake valve or the cylinder, it kind of blocks the flame travel, which impairs the burn path thus causing a loss in power. It can be a 6 - 8 horsepower difference in some engines by indexing the plugs.
Don't run a high volume oil pump. Most street and street / strip guys believe you just HAVE to run a high volume oil pump. The reality is, you don't! Standard oil pumps pump plenty of oil and have plenty of pressure to support most mild performance engines up to 6,000 RPM. By installing a high volume oil pump you increase the drag on the engine while it is trying to turn that pump to push that additional oil which robs you of power you didn't need to lose.
Another way to gain a substantial amount of power is to remove your power steering pump and convert your car over to manual steering. I don't recommend this for daily drivers because the steering will become harder. Power steering pumps can easily suck-up 20 to 30 horsepower. Don't believe me? Turn your steering wheel a little, side to side, while your engine is idling and hear the idle drop a hundred or so RPM. How much horsepower do you think it takes to lug your engine down that far? Yeah... about 20 or 30. So you say you aren't "steering" while you're driving down the drag strip? Well, every time your car gets squirrelly off the line, you have to "correct" it by steering, and there went 20 to 30 horsepower. If your car doesn't get squirrelly, maybe you should call us and order a BAD-ASS Engine and then you’ll be fish tailing! LOL
Another way of gaining about 8 to 10 HP is by draining about 1 quart of oil out of your oil pan. Most cranks dip into the oil pretty deeply and that‘s why windage trays work so well and get you more power at RPM. They keep the oil away from the crank which makes less drag. When the engine is full of oil, it is like wading through knee deep water. Try to run while in knee deep water. It isn’t that easy because of the drag the water puts on your body. When you drain out 1 quart, this makes the crank less deep in the oil as it spins. It’s now like walking in ankle deep water. Try to run now, it’s a LOT easier than it was when it was knee deep, right? Well the same principals are at work here as well and will make you free power. Switching to a slightly thinner oil is another way of gaining power. This puts less drag on the crank as it dips through it in the pan as well as makes the oil pump spin easier and much more free which in turn, takes less power to spin. Only do the power steering belt trick and these two oil tricks at your own risk. If you crash because you couldn’t steer because your steering was too hard while the belt was off, that is your fault, not ours. If you wipe-out your engine because you drained too much oil out or ran too thin of an oil to keep your engine protected, that is on you and not us. If you don’t know exactly what you are doing, don’t do it!