Gear Drives

[chevydeerhunter]

First off, brand new to this forum, but not to drag racing. Now that the mutuals are over, got a question from another forum about gear drives. When I raced, I used nothing but a timing chain setup and a few people I knew used gear drives on the street. Right to it though, are they worth the money just to keep a wee bit better time? How does the top end hold up over time with a gear drive setup? Do they wear well for street use?

Thanks in advance!

[John_Heard]

I have one in my suburban, the guy I bought it from put it in there when he rebuilt the motor. I believe it's one of those "Silent" models because it's not as loud as some I've heard. However it continually annoys me because it sounds like a dry steering pump. This motor has about 20,000 miles on it now, so I would say they are reliable, I just don't like the sound of them myself.

For street/strip use I would just use a chain... unless you like the sound of a dry steering pump

[Bobalos]

IMO, not worth the hassle.

Bob

[chevydeerhunter]

I also heard that they shouldn't be used on late model computer controlled vehicles because they can confuse the sensors somehow. Which one's, not really sure but I would suspect the knock sensor. Am I right?

[Bobalos]

Ive heard the same rumor, but I had a buddy on the 3rd gen site that ran one & it did not mess with it. Heck I ran a Rattler harmonic ballancer on my stroker motor & it was not until 2 years latter that It kind of hit me. "DUHHHHHHHHHHHHH, put something that rattles, in a motor with a knock sensor". it was totally the wrong harmonic, it never picked up a single rattle from it. but BOY did it pick up detonation when you set the timing up 10+* too much. LOL.

Bob

[moeraces]

I,ve used them on the street and strip , i agree they are not worth the hassel , also found that they transfer harmonics off the crank, to the valve train a hi-rpm : ie above 8000 rpm.causing hi-rpm pop, changed it out , to dbl roller chain , hi-rpm miss went away. Later guys , flynmoe

[sixty_foot]

unless you consider using a belt gear drive, dont do it. the timing chain acts as a buffer to dampen and absorb the crank harmonics that can transmit up to your valve train, causing valve lash adjustments and spring failure.consider this.....you cannot put a gear drive on a stock computer engine, because the increase in the harmonics is such that the knock sensor will pick it up and automatically retard your timing.........retarded timing=poor performance. (on a regular engine,this will show up as spark scatter on your total advance) the only exception to this, is the belt drive, and that is quite pricey depending on your budget. my advice would to invest in one of the comp cams timing chain sets and avoid all the headaches.

[teagersnova]

If you use one make sure that you use a harden key for the key way. A friend of mine just stripped the key and bent all the valves. Not worth the trouble!!!!!!!

[DriveWFO]

I have a Pete Jackson "noisy" gear drive for sale if ya want it.