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Old 01-17-2010 | 11:00 AM
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Originally Posted by ezstriper
Don't care what jackson says...dyno says otherwise....NO real race engines will be found with a gear drive in a N/A app.

Thats a really tall statement- your sure you want to go with that?


Heres are some quotes and links.

http://www.wesmarracing.com/components_sw.htm

The main advantage to running a real gear drive , is the capability to control cam end play on roller cam engines , something that is difficult to do using a chain drive . Roller cam engines have a great amount of forward thrust , and this will affect ignition timing if the cam move forward too much (timing will retard as RPM rises). The other advantage is , you don't have a chain stretch problem with a real gear drive . There is absolutely no problem in using this type of gear drive in a circle track engine .

We also use the Jessel belt drive . It has the same advantages as the Shaver/Wesmar drive , in respect to the ability to control forward cam thrust . But the belt's will also stretch over time , though not as much as a chain .

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




There is a lot more out there.

Uncle Dave
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Old 01-21-2010 | 08:49 PM
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I run Milodon Gears in my 600 inch Fords and I do have harmonic problems at 6500 rpm. Have upgraded all the valvetrain to overcome and it helped, but not entirely. I am using belt drives next go around.

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Old 01-24-2010 | 01:35 AM
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Originally Posted by 2112
I run Milodon Gears in my 600 inch Fords and I do have harmonic problems at 6500 rpm. Have upgraded all the valvetrain to overcome and it helped, but not entirely. I am using belt drives next go around.

.
wow a 600 , cool ill bet that mill really honks 2112

We had a gearte 420 sprint engine on alky spinning 8 - but thats a lot less mass.

UD
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Old 01-24-2010 | 08:08 AM
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Yes for sure, I have a sonny's 565 and a reher/morrison 565 big chief, that we run in my top sportsman car, and I will say again NO big name race engine buiders use gear drives in N/A apps, when they go away from chains it's to jessel belt, the RM engine makes over 1000 HP on a single carb, both still running a chain...been doing engines and racing for years and I will stand behind my tall statement....If you don't believe me go to sonny's, reher/morrison, or shafiroff race engines web sites, ck out their specs, you will not find a gear drive used or offered !!! those quotes are from people trying to sell gear drives and blowing smoke...they talk cam retention....every block now using roller cams already had a retainer plate...

Last edited by ezstriper; 01-24-2010 at 08:13 AM.
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Old 01-29-2010 | 12:37 AM
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Originally Posted by ezstriper
Yes for sure, I have a sonny's 565 and a reher/morrison 565 big chief, that we run in my top sportsman car, and I will say again NO big name race engine buiders use gear drives in N/A apps, when they go away from chains it's to jessel belt, the RM engine makes over 1000 HP on a single carb, both still running a chain...been doing engines and racing for years and I will stand behind my tall statement....If you don't believe me go to sonny's, reher/morrison, or shafiroff race engines web sites, ck out their specs, you will not find a gear drive used or offered !!! those quotes are from people trying to sell gear drives and blowing smoke...they talk cam retention....every block now using roller cams already had a retainer plate...

What are the sprint guys using these days?

Isnt wesmar part of Shavers engines?

I only build an engine every few years, Im willing and wanting to be schooled.

Interesting thread going on right now. http://www.offshoreonly.com/forums/g...-cam-gear.html

UD

Last edited by Uncle Dave; 01-29-2010 at 12:58 AM.
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Old 01-29-2010 | 06:29 AM
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yes, talked to vinny on that....I still feel something else caused the failure..but as with any part now, with so much chinese junk all thru our industry in brand name parts you never know what kind of crap you are getting...even buying some "brand" name componants...Rob
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Old 02-01-2010 | 09:53 AM
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Originally Posted by ezstriper
yes, talked to vinny on that....I still feel something else caused the failure..but as with any part now, with so much chinese junk all thru our industry in brand name parts you never know what kind of crap you are getting...even buying some "brand" name componants...Rob
Arent there 2 guys in that same thread with the same problem!

So you wouldnt just use a gear drive?

I know the jesel belt drive is excellent, but you have to change every x hours , in a race rig no biggies in a pleasure rig - not so cool.

Ive always had great luck with them, but I never have run 600 inch engines like 2112.

UD
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Old 02-01-2010 | 10:33 AM
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I've been using the jackson gear drives for years. as i've done some circle track racing. one theory i've heard is ability to have dead-on timing with no spark scatter which chains give you upon increasing amount of slack in chain from stretch. and the fact that the gear drive gives you an allmost bulletproof drive. limited life with a belt concerns me. also I was questioning the other guys have had with chain drive failures.
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Old 02-01-2010 | 02:11 PM
  #29  
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I've been running a Milodon gear drive in my 598 since 2002 and haven't had a problem. The timing is very stable and it works well with my EFI.

Last edited by GPM; 02-02-2010 at 04:15 PM.
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Old 02-09-2010 | 11:15 AM
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IF you want to run a gear drive, run a Milodon, or any other
three gear with a fixed idler, for that matter! those "dual idler"
floating "bounce around" types are junk! I can't count how many of them I have pulled out of engines, where the dogbone
idler plates were already worn out and sloppy, OR where the
idler pins (that are supposed to locate the unit ) were spinning
with the gear, not only "machining" a nice spot faced looking
hole in the front of the block, but also depositing the shavings
in your oiling system! have also seen them tear up front cam
bearings! + they don't offer any better cam walk protection
than a chain w/ a button! run a 3 gear, true roller, or belt,!
+ the pj's instruction sheet also mentions NOT for use above
6500rpm, or somthin' like that!
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