What would be the best choice for hp and life? I know chains will stretch over a period of time but is there any advantage between the two?

http://www.chevelles.com/forum/ultimatebb.php/topic/4/19945.html

Personally, I would use a chain for street/strip, and a belt drive for all out racing.

I've installed both but some where it seems I read that harmonics can be transferred with the gear drive and there are some other issues as well.My feeling is a good quality chain and sprocket combo is an economical way to go. I've never had a problem with a good chain getting real sloppy.Yes the ultimate setup is probably a belt drive but they are pricey.To answer your question,frankly,use a good chain :cool:

i have and do run both chain and gear drive.....some readings have said there are hormonic issues with gear drive....

i first bought the gear drive for noise...and that purpose only....and of course that was maybe 13 years ago....but now that i have somewhat of a serious motor with alot of dome and a lot of lift....i feel better knowing the cam timing isnt going to change any with the gear drive and maybe there is a less chance that it would break... over a chain....

i think for the most part a nice quality chain is hard to beat.....most double rollers i have been able to go from engine to engine.....i guess if you got a gear drive laying around to use in a moster motor with big parts i would say use it......but i dont think i would go out of my way again to buy another......i'll stick with chain...besides more in my price range anymore

I've got a Pete Jackson "noisy" gear drive in my 388ci. I like it. Only draw back is that you can't really hear it, and if you really pay close attention to it, it sounds more like a bad alternator then a gear drive :rolleyes: Other then that, I've never had any problems with it smile.gif

I have a Milodon gear drive in a 427.
It works well.A good gear drive is fine.
Would I use a cheap import, no.
For most guys, a Cloyes double roller chain is
plenty strong enough.I would stick with billet
gears myself as I have split cast gears in the
past.

I agree with whats been said so far. A good chain is good enough for me. Ive heard about the harmonic issues with the gear drive reducing camshaft and bearing life, and it makes sense to a degree. I mean, the noise of the gear drive should indicate that its operation is not totally smooth, and there has to be some sort of a vibration/harmonic action going on there somewhere along with the noise. But how much does it actually affect the life of the valvetrain? Who knows. I couldnt tell you if anybody ever took the time to test a gear drive against a good chain to see how long the same cam lasts in either conditions. It would not surpirse me if has always bee just a fairly good assumption(or myth) based on what I was sayin earlier(gears make noise so the cam has to be absorbing something). Or maybe somebody has uses some accurate machinery to measure the harmonic output/absorbtion with a gear drive, but once again, I dont know. I bet that even if anybody has taken it that far to prove the existance of the harmonics, they still didnt do any kind of back to back comparison to really see how much it really affects cam life compared to a chain. I stick with a good chain just so I dont think about it too much.

A chain will absorb many vibrations that a gear drive will not.....stick with a high quality chain.

Correct me if I am wrong but nylon gears are used to do just that as well.

It just seems to me that if gear drives were the hot ticket everybody that builds comp. eliminator,super stock ,pro stock, NMCA,NSCA stuff would probably be using them.......but we know they dont....... :cool:

There's some debate on realoldspower.com about the Pete Jackson style gear drives breaking camshafts. Seems the twin idler gears tend to shift position so that one of them wedges between the cam and crank gears, and forces them apart. Over time, the cam breaks from fatigue, I guess.

Chain drive for me. Belts are too expensive.