Thread: Pro's and Con's of timming gear drive

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I would like to hear every one's good and bad experience's with timming gears!!! I've heard that they wear engine parts prematurely. I've now had a engine shop tell me that the gears
push up on the cam,wearing the top of the cam bearings out.
Tell me what you think about timming gears or your experience
with them!!!


~ Vegas ~

I've been workin on Dirt Late Model racecars for over ten years now, and I have yet to talk to one single engine builder who uses them. We're talking $30k, 800hp engines here, too. The builders all agree that a chain, or better yet a belt drive, is the way to go.

Go to any engine builders seminar. You will not find any Pro builders that use gear drives. All you have to do is watch the computer simulation presented by one of the major cam companies and you will never use one again. OLD TECH.

Gear drives transmit all vibration and harmonics from the rotating assembly, directly to the already taxed valvetrain. The pushrods and valve springs look like tuning forks, high frequency vibes.

When asked, why do you still sell gear drives? Answer is always: The kids buy em!!!

I put a timing gear specifically for the vibration! We had a long trip coming up and we did not have time to swap the engine. The timing gear, with a new camshaft kept the oil pressure up long enough to make the trip. It was very annoying, the noise, and the gear ate almost through the timing gear cover.
Upon getting to our destinatin, we rebuilt the engine, replaced the gear with a chain, and it runs great now.
I have wondered if there is actually an advantage to using a gear vs a chain, or belt. I have never had a chain go, or jump a tooth, and I wonder if any difference is noticeable when running.
I had a quiet gear set, and the vibration in the engine was amazing! I cannot see using one in a vehicle for daily driving for any length of time.

I have never heard anything good about them other than they sound cool for the first couple of days!! I cannot imagine having to listen to one all the time! Stick with a double roller chain and you will be happy!

Yep; So far the nays have it.
I purchased a timming gear for my 351 cleveland/boss a couple
of years ago,while I was stocking up on the good stuff.
I had read a couple of articals about degreeing wheels and timming gears for precise engine tunning. Now I have never
run a gear in any of my engines, I've allways run double roller
chains. I've onlly ever had, one chain jump time on me.
Well maybe that Pete Jackson Gear Drive will look good on the
garage wall. HE! HE! Hey some poeples picture's cost more then $250 dollers, Hey look how ugly some of that new art looks.
What should a old gear heads art work look like, Right!!!
Looks like I'll be using a double roller , Thanks for your Input.


~ Vegas ~

If you put a timiing light on a engine that has a gear drive you will notice the timing is all over the place not being steady at all. Go with a chain or belt drive is even better.

I've got a gear drive in my 69 Firebird. The motor was put together by an old school drag race shop owner in Kinston, NC(Jackson automotive performance) originally(3yrs. ago) for his own use. It is a 12.5:1 compression 383 stroked chevy, 461 fully ported heads, big solid lifter cam, stud girdle, team G intake, modified 750 holley, super comp headers, 3" exhaust, etc, etc. (runs high 11's on 255/60/15 basic STREET tires at 3600lbs. with me in it) He builds mostly 1500+ hp stuff and has been racing competitively since the late 60's...the 383 was his version of an old school street/strip motor. By all accounts, I have every reason to believe that he knows his s**t, and he would be the first to mention that he intentionally built it "out of date" in a bit of a nostalgia thing. As far as how it sounds...the gear drive is very noticable even over the 3" exhaust, high compression, and solid lifters. Is sounds like a cross between a blower and a turbo spooling. It is the most obvious at idle. Anyone that has heard one before can tell right off that it has a gear drive. My new motor is finally ready: 406 small block, 10.5:1 comp, pocket ported 461 heads, DOUBLE ROLLER chain, etc. One of the things that I will miss the least about the 383 is the sound of that gear drive timing.

My understanding is that the gear drive is more of a style/attitude thing today rather than the best thing out there. Belt drives have certainly taken that over in the real high end stuff. Hope this helps...just my 2 cents.

George

yup, i made the mistake of putting a gear drive in the first motor i built... which happens to be the one currently in my daily driver.... sounds cool the first day or so..... now i just crank the stereo up to get rid of that annoying noise.... cant wait til i install my double roller

Originally posted by vara4
Yep;
Well maybe that Pete Jackson Gear Drive will look good on the
garage wall. HE! HE!


~ Vegas ~

Hey Vegas, You can always mount it on a wooden plaque and turn it into a clock with the guts out any battery operated clock on the market. Hehehehehehehe

haha yeah he could but there would be one problem.... he'd either have to use a 24/hr clock and connect it to the cam gear and put the hands on the crank gear, so it'd function as a 12/hr clock... or vise versa

Oldf100fordman:That's a great Idea, I like it!!!
Thesals; Your allways trying to make me strain my brain, but that ok it's all good, and it keeps me on my toes. This is a great idea and won't be shared with common folk, It will go up in my new shop once it's done getting built. This way only fellow gear heads will get to enjoy gear head art work. And it's a steel for only $257 dollers, some guys pay thousands for good art.


~ Vegas ~

PS tried to answer earlier but my power kepped going out.
Dang it!!!