Author Topic: Dual Idler camshaft gear drives - generally "bad" or "good" idea for a race SBC?  (Read 712 times)

Offline Jaychalmers

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  • Your Best Time: 6.02 1/8 mile
  • Your Engine: 388 Enderle injected SBC
  • Your Track: Music City Raceway
  • Your Vehicle: Home built FED
  • General Location: Tennessee
I've seen a lot of negative thoughts about dual idler cam gear drives in a race motor, but I've seen a couple of positive posts as well.  Since Pete Jackson drives can only be found used, I've just purchased a "USA-made" SA Gear dual idler drive for about $140.00.  The crank keyway (and/or timing marks) apparently are not accurate, but by experimenting with the bushings (and the cam gear position), I'll be able to get the 4 degrees of net cam advance I'm looking for.  However, due to negative comments from engine builders and racers, I'm getting the feeling I'd be better off (and safer) with a "higher end" race roller chain and adjustable cam gear set-up such as Comp Cams "ultimate" race roller chain which is about $180, or maybe a Cloyes unit?  A $1K Milodon, Jesel, or Summers Brothers unit is simply outside my modest race parts budget. 
Any thoughts?
Thanks.     

Offline dusterdave173

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  • Your Track: Mooresville, NC
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You should not use that--it is poorly made--It was made to make noise for cruise in guys--not to put in a fine race engine--use a very high quality chain and gear set--Cloyes Hex-adjust is a fine piece and the Aussie sets have a premium german chain  the chain is the deal don't us one from India etc
good luck
I have always had a fascination with fast cars at the expense of more normal character development

dreracecar

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The basic premise of the dual idler is fine. the only reason for 2 gears is that it keeps the primary load gear in contact without falling out.  As far as the quality of the part--I dont know. But I have been running the same Summers unit for over 25 years now

Offline OldSchoolHP

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Ive had a PJ gear drive in several different experimental builds of my drag race 9000+ rpm SBC combos from a N2O 327 to a Alcohol 434 and its always been perfectly in time and ran great. No issues. Would you reuse a CHAIN SET?? All the negative hype is from spode lipped mommas boys that's mom oiled their bike chains for them growing up, so today they are just plain scared of those crazy gears. Some things requires skillset that's outside of the typical magazine certified builder. Set it up right and it will run forever.