Dogbone timing gears
Drifting
Joined: Jun 2025
Posts: 1,715
Likes: 597
Looks good on paper, but in practice; not so much. They're Very Noisy. Emulate "blower whine". Approaching regrettable.
And entirely Unnecessary in any but Heavily modified motors with huge cams & huge valve springs.
Also, avoid double row roller chain sets; also unnecessary & some Require clearancing/grinding face of block.
Per your profile: Seems yours has little to no internal engine modifications.
? Which motor does your '72 have ?
Most likely best-served by a Quality Heavy-Duty, Single-Row roller chain timing set.
Melting Slicks
Joined: Apr 2021
Posts: 2,709
Likes: 2,156
From: Minnesota
From the experiences of people that have done it online, it seems the general consensus is that it’s a labor and money intensive investment with the only benefits being in race engines where incredibly precise valve events are needed. You don’t have to worry about a timing chain stretching, but seriously, that’s really only a problem after tens of thousands of miles or decades of use. Like others have said, they do sound neat with the straight cut gears, although some people might be disappointed when you pop the hood and there’s no supercharger there.
Last edited by Piersonpie; Aug 11, 2025 at 07:41 PM.
Pro
Joined: Nov 2023
Posts: 702
Likes: 335
From: Aubrey TX
I used a set in a moderate street 289 Ford I rebuilt over 20 years ago. Took it out the next weekend and replaced it with a double roller chain set. It was so loud, you could hear the car coming 2 blocks away.
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 2,814
Likes: 469
From: Wichita Kansas
^^^THIS^^^
Looks good on paper, but in practice; not so much. They're Very Noisy. Emulate "blower whine". Approaching regrettable.
And entirely Unnecessary in any but Heavily modified motors with huge cams & huge valve springs.
Also, avoid double row roller chain sets; also unnecessary & some Require clearancing/grinding face of block.
Per your profile: Seems yours has little to no internal engine modifications.
? Which motor does your '72 have ?
Most likely best-served by a Quality Heavy-Duty, Single-Row roller chain timing set.
Looks good on paper, but in practice; not so much. They're Very Noisy. Emulate "blower whine". Approaching regrettable.
And entirely Unnecessary in any but Heavily modified motors with huge cams & huge valve springs.
Also, avoid double row roller chain sets; also unnecessary & some Require clearancing/grinding face of block.
Per your profile: Seems yours has little to no internal engine modifications.
? Which motor does your '72 have ?
Most likely best-served by a Quality Heavy-Duty, Single-Row roller chain timing set.
Tech Contributor
Joined: Aug 1999
Posts: 14,379
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
That's been around for a very long time. It was known as a "Jackson Gear Drive" in the 1970's. It serves no practical purpose whatsoever other than making your car sound like it has a blower. It wasn't used by any serious racer - a good chain is much more efficient.
Le Mans Master
Joined: Mar 2004
Posts: 7,493
Likes: 1,502
From: Little Rock AR
I had one a long time ago. This was before they made them in both quiet and loud versions. They sound a bit like a bad power steering pump that is low on fluid. Sold it and never thought about it ever again.
I like the GM HD Morse chain setup. No plastic gears or block clearancing required. No need for more than that unless you are going roller cam.
I like the GM HD Morse chain setup. No plastic gears or block clearancing required. No need for more than that unless you are going roller cam.
Last edited by stingr69; Aug 15, 2025 at 07:12 AM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Le Mans Master
Joined: Oct 2010
Posts: 6,936
Likes: 848
From: melbourne florida
2023 C3 of the Year Finalist - Modified
They do make sets that are quieter. The argument about timing accuracy I just say it really isn't that big a deal. I'd use a belt drive before I'd use a gear drive.. stick to a good roller chain.. Bill Jenkins used the GM nylon coated gear sets to dampen harmonics but he wasn't concerned about running thousands of miles. Running a gear drive won't buy you anything .
Drifting
Joined: Jun 2025
Posts: 1,715
Likes: 597
OP kansas123
For your apparent needs, a good quality timing set (aka speed set) can be had for less than $25 to over $250. Heck, Melling even has a timing set (P/N 40520) w/ a HY-VO® aka Morse® aka Link-Belt® chain; sells for nearly $400. At one time, sets of that grade were OE in some GM race crates.
My suggestion for pre-86 Gen I sbc is a Large-Pitch, Heavy-Duty Single Row timing set: single-row chain w/ large diameter Seamless rollers; Cloyes P/N C-3055 under $40 OR Melling P/N 40500 under $65.
For your apparent needs, a good quality timing set (aka speed set) can be had for less than $25 to over $250. Heck, Melling even has a timing set (P/N 40520) w/ a HY-VO® aka Morse® aka Link-Belt® chain; sells for nearly $400. At one time, sets of that grade were OE in some GM race crates.
My suggestion for pre-86 Gen I sbc is a Large-Pitch, Heavy-Duty Single Row timing set: single-row chain w/ large diameter Seamless rollers; Cloyes P/N C-3055 under $40 OR Melling P/N 40500 under $65.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
Likes: 9,348
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
I put one in a small block in the 90's and it was loud but you dont get any chain slop and it will never fail. Back then they were all the same and very loud. I have one currently in my 68 427 and its advertised as a quiet, I beleive it was PRW. It was very expensive compared to a chain, but there is no slop, no lash and no way for it to fail. It is still audible but once the fan comes on I cant hear it and when I get above idle I cant hear it above my pipes....
more of a cruise speed
more of a cruise speed
Drifting
Joined: Jun 2025
Posts: 1,715
Likes: 597
I put one in a small block in the 90's and it was loud but you dont get any chain slop and it will never fail. Back then they were all the same and very loud. I have one currently in my 68 427 and its advertised as a quiet, I beleive it was PRW. It was very expensive compared to a chain, but there is no slop, no lash and no way for it to fail. It is still audible but once the fan comes on I cant hear it and when I get above idle I cant hear it above my pipes....
https://www.youtube.com/shorts/Oqzo70fzV-o
https://www.youtube.com/shorts/N4BDrviAb4Q
more of a cruise speed
https://www.youtube.com/watch?v=-hrmZh1ZRhY&t=19s
https://www.youtube.com/shorts/Oqzo70fzV-o
https://www.youtube.com/shorts/N4BDrviAb4Q
more of a cruise speed
https://www.youtube.com/watch?v=-hrmZh1ZRhY&t=19s
Then, as he said: Hey y'all, watch this (no way for it to fail) !
Ya might not hear it while inside side-piped C3 cabin's reverb-chamber, but Everybody outside does.
I have serious hearing deficits in upper registers; I hear the gear drive whine as recorded inside cabin.
*seems Melling did offer its version of sbc gear drive (P/Ns 48400 & 48400Q) But seems Melling has discontinued them.
If so, wonder why no more Melling sbc gear drive ?
I like gear drives; in their natural place e.g. chevy & ford inline 6 OE helical sets.
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,082
Likes: 4,431
From: Marlton NJ
Very old school.
I remember dyno tests from back in the day, said they actually cost power due to vibrations affecting timing accuracy & fluctuations.
Serious racers these days use a belt drive for that exact same but reverse reason, it dampens timing variations.
Or they just go to a crank trigger for the same reason, better timing.
I remember dyno tests from back in the day, said they actually cost power due to vibrations affecting timing accuracy & fluctuations.
Serious racers these days use a belt drive for that exact same but reverse reason, it dampens timing variations.
Or they just go to a crank trigger for the same reason, better timing.