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Author Topic:   gear drives vs. chain drives
driver27
Dirt Full Roller

Total posts: 69
posted April 12, 2002 01:51 PM
Ok, im interested in which is better, a chain drive timing set or a gear drive timing set. Unfortunately a belt drive system simply is not in the budget. What are the pros and cons of each system. Steve, i'd really like you input on this one.

Thanks Van

sdhnc29
Dirt Freak

Total posts: 467
posted April 13, 2002 01:31 AM
Hey Van ,

There is no comparison between a gear drive and a chain drive , the gear drive is better !!! I say the gear drive is better , provided you invest in a good gear drive ! All of the engines that build , use either the Shaver/Wesmar gear drive , or the Jessel belt drive . The advantages are of the gear drive or belt drive are simple . The main advantage is the ability to absolutely control cam walk ! This is especially vital in roller cam applications when the cam thrust can reach several hundred pounds . Once you have controlled the cam walk with the gear drive , you will now have more accurate ignition timing and you will not see the timing retard at higher RPM . The potential horse power gain's from controlling cam walk will far out weigh any horse power loss you will see from the friction gained by the gear drive . Another advantage is the fact that the gear drive will last just about forever , provided it is set up correctly .

The advantage of the chain drive in my opinion , is only the cost .

For the average racer who is on a very tight budget , I would still suggest using the chain drive if your not using a roller cam set up . For hobby stocker's or street stock racer's , there money would be better spent in other area's . But if a Jessel belt drive , or a top of the line gear drive is in your budget , then I would invest in one !! I would also suggest staying away from any of the duel idler gear drives !!! If you have a choice between a chain , and duel idler gear drive , then go with the chain !!!

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780

driver27
Dirt Full Roller

Total posts: 69
posted April 15, 2002 07:41 AM
[Ok so what Im hearing is, A good chain drive system is still a decent option for a solid lift cam. Excellent response, just what I was looking for. I'll be calling you soon concerning ordering me a crankshaft, just need to round me up a block yet. Thanks a ton.

Van

sdhnc29
Dirt Freak

Total posts: 467
posted April 15, 2002 12:21 PM
Yes Van , a good chain drive is still a decent option for a flat tappet cam . But I will always suggest the Shaver/Wesmar gear drive , or the Jessel belt drive to those who have this option in there budget .

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780

Monster
Dirt Maniac

Total posts: 135
posted April 17, 2002 10:08 PM
Any opinion on the Comp Cams(Bo Laws) wet belt drive?

Pickles
Dirt Maniac

Total posts: 144
posted April 30, 2002 07:51 PM
Plus the whine of a gear drive really sounds neat!

sdhnc29
Dirt Freak

Total posts: 467
posted April 30, 2002 11:05 PM
Sorry Monster , I never saw your question about the Comp Belt drive . I personally have never used one of the wet belt drives . So my only opinion will come from my belief that I would not want a belt running in oil . It seems to me that every time the belt comes in contact with the gear , it would have to push oil out from under it's self . Without testing this set up on a dyno mule engine , I really could not tell you the exact gain's or losses by using one . I'm happy using the dry belt Jessel drive , and the Shaver/Wesmar gear drive .

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780

Monster
Dirt Maniac

Total posts: 135
posted May 05, 2002 09:09 AM
I would rather run the Jesel setup myself, but though they are technically legal at most of the tracks we run,no one has one, and if we showed up with one, they would scream "Too much money, yer ruinin' the class!", and be ruled illegal right away, I'm sure. On this wet belt, the oil situation is addressed by cutting small escape grooves at the bottom of each tooth on both pulleys, and matching holes in the guide thingies. Cost(new) is slightly higher than a used Jesel setup, and is completely hidden under a stock front cover. Very stealthy.

Monster
Dirt Maniac

Total posts: 135
posted May 05, 2002 11:01 AM
At most tracks we run, belt drives are technically legal, but no one runs one, and if we showed up with a Jesel, people would scream "Costs too dang much, yer ruinin' the class!", and they would be declared illegal right away, I'm sure. The wet drive is very stealthy(will fit under a stock timing cover), and the oil situation is addressed by grooves cut at the bottom of each tooth on the pulleys, and matching escape holes on the guideplates. Cost(new) is right in line with a used Jesel setup.We're giving one a chance this year, we'll see what happens.

Monster
Dirt Maniac

Total posts: 135
posted May 05, 2002 11:03 AM
Sorry for the double post, but for some reason the first one did not show up until I posted the second one! DOH!

dirtracer14
Dirt Freak

Total posts: 499
posted May 05, 2002 08:26 PM UIN: 23443678
What is the cost of the gear drives that you are talking about? Do you sell them and have them on the shelf? I am eating up dist gears and cam gears when i pulled the cam out i saw marks on the timing cover?? This is a flat tappet with no button. I am now having to order a new cam and lifters and dont want to keep eating up gears. The chain drive i had on there was a little loose for only 45 laps i really think i need to go with the gear drive but only want to do it once Thanks

sdhnc29
Dirt Freak

Total posts: 467
posted May 06, 2002 04:03 PM
Hey dirtracer14 ,

I sell the Shaver/Wesmar gear drive for $585.00 . Yes , it will prevent the cam walk situation you are experiencing !

Steve

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780

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