Was looking into this years back. Was wondering if there are any benefits to using a belt instead of a chain for the cam/crank? And if one was ever fitted to an LT1?

Edit: nevermind. Forgot about the optispark. Also found this thread: https://www.camaroz28.com/forums/sho...d.php?t=667770

 

Engine Masters magazine, Summer 2007 issue, did comparison testing of timing sets on an 440 Mopar. They used a chain drive, a belt drive, a fixed-idler gear drive and a dual-idler gear drive. There was no significant advantage on the HP side - average HP varied by less than 1HP and average torque varied by less than 1 lb-ft (on a 630HP NA engine). They found the Jesel belt easiest for adjusting cam advance because the Jesel mounts externaly.

 

the fastest lt1 fbody was using one

 

I'm surprised the gains with the belt were not greater than that. Then again, I wouldn't think it would be enough to get an accurate reading on the dyno. I would have quessed at least 3-4 HP, but what do I know.

 

I belive the tests. A fresh chain, gear drive or belt drive won't show hardly any deflection/timing losses, and the power needed to turn a valve train is so substancially more than any tiny weight savings as to be insignificant.

Possible advantages:
1) external belt drive could be easier to dial a cam or replace a broken or stretched belt.
2) belt drive "could" be made fairly thick to increase durability.
3) belts have naturally more harmonic dampening, but LT1's don't run rear mounted distributors, just oil pumps, so I doubt there will be many gains there. If it really bothered you it'd be easier to do an external wet, or a dry pump system and get it off the cam entirely.

With LT1 computers running out at ~7200 rpms, the high rpm vibration issues other small blocks see at 8000-9000 just don't exist at say 6500. Cost and fab would be far greater than any real gains. Spend the money on a dry sump system, or lighter valves, or beehive springs, or... well you get the idea.

Unless you run a carb'd LT1 or an aftermarket PCM and intend on breaking 7000rpms you're probably better off with just a LTx Extreme Dutychain and a billet sprocket set... although the ability to dial a cam easily would be nice for racers tuning new set ups... but that's an awefully expensive upgrade (Jesel belt drive + aftermarket PCM)