We hear statements this all of the time; "I have to have a gear drive because I'd break timing chains". That's an interesting statement because I have never seen a timing chain break unless something catastrophic happened to the engine. If someone's engine is actually breaking the chains, then obviously something's not right. It isn't the timing chain's fault though and it certainly isn;t because the engine is "too radical". On big, bad to the bone, serious engines making between 1,500 and 3,000+ HP, we use Jessell belt drives. So with that, people that say their 350, 400 or even 500HP engine would break a timing chain just seems funny when we have never had a failure with a timing chain or a rubber belt drive, and that includes engines with ultra heavy, triple valve springs with three and four times the spring pressures than any basic performance spring, and with cams that have lifts in the .850+" area. Don't get us wrong, there's nothing wrong with running a gear drive if you like the sound. We install them on quite a few engines at the customer's requests. We just don't prefer them over a chain, because we like to hear the natural sound of the engine.