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Keith
02-19-2005, 06:54 PM
Anyone ever hear of problems running a roller cam in a big block and using a gear drive?

Blown353
02-19-2005, 07:44 PM
It's typically said that the harmonics induced by a gear drive will contribute to premature failure of the roller bearings in the lifters. I don't have any data to support this conclusion, I've just heard it from many people who don't have any real life experience to back this up. So it may be true or it may be an "old wives tale"... hopefully someone with some real answers will chime in.

I'm not a huge fan of gear drives to begin with, both for the noise and the harmonics they introduce into the valvetrain. You're much better off with a good true double roller chain or a belt drive. The belt drives have been out long enough now to prove themselves reliable pieces, they even have some street versions. Just run a "dry" belt setup with a debris shield and check it every 10K miles or so. Easy cam timing adjustment, even less harmonics transmitted to the cam/valvetrain than a chain, etc. A bit more to go wrong than a good chain, but they're good pieces.

Troy

spaztikatik
02-19-2005, 09:43 PM
I'm using a Comp Cams wet belt-drive unit for my 420, and the only thing they reccomend for normal daily street use and light racing is to replace the belt once a season, or 10k miles like Troy says. We'll see how it all work out once they finish building it and sit it on the dyno in 3 weeks... :thumbsup:

Keith
02-21-2005, 04:49 PM
I'm using a Comp Cams wet belt-drive unit for my 420, and the only thing they reccomend for normal daily street use and light racing is to replace the belt once a season, or 10k miles like Troy says. We'll see how it all work out once they finish building it and sit it on the dyno in 3 weeks... :thumbsup:

I was considering the Comps version until I saw the price and I started thinking how much I had spent for other things on the car... $1200 is steep but really, can you put a price on reliability? :D