Like the title says, I have a BOP 8.2" 10-bolt under my '64 Special. It currently has 3.08 gears. I'm seeing confusing data with regards to availability of a deeper (3.36-3.55) gear set availability. I see some data that suggests I need a carrier that originally came with at least a 3.23 gear set, I've seen others that claim to fit as is... What's the real scoop? I'm open to any vendor, just want to find something that will work!
Hi, I believe your correct, my understanding is 2.78-3.23 is a 2 series and 3.36-430 is a 3 series there might be a 1 series for 2.41-2.56 but not sure 3.23 is stock ratio for a stick 300 or V6 I'm running 3.55 with 245/60r14 and 80mph is 4000rpm, 70mph is 3500rpm Regards,
I got a 323 possi from Jim Monazz here on the board, Ten plus years ago and still going strong,Check him out, Real nice guy also
I had a 3.55 with an Eaton post built earlier this year. Love it. My axle came out of a 1964 Cutlass.
CORRECT DATA for all 2.56 - 2.78 is 2 series (factory only no aftermarket carriers avaialble) 2.93 3.08 3.23 is 3 series (Auburn unit only aftermarket) 3.36 3.55 3.73 3.90 4.10 4.33 4.56 4.88 5.13 and ^ 4 series carrier (eaton & Auburn units available) That will do it for the 1964- 1967 Buick and Pontiac rears. (Olds used the B or the P in these years till they made the 12 bolt Olds rear which had the 12 boolt cover and 10 bolt ring. 67-70 era ) Jim JD Race
So based on the info from Jim (thanks), if I want 3.55 gears, I need a 4-series carrier. That seems somewhat daunting - especially since I need the narrower 64-67 unit. I'm not too concerned about revs, since I have a turbo V6 GN engine/trans in my car (which means 0.67 overdrive in the 2004R). With my current setup, I'm turning a little over 1900 rpm at 70 mph. Another option is a Chevy carrier, although I certainly prefer bolt-in axles vs. c-clip. I suppose I'll have to keep my eyes open for a usable core.
Most newer rears, including the 8.5 are ONLY 1/2" wider on each side for a total of ONE INCH. Whats the big deal????
Just use the rear in the car now. This should be what you need. Auburn, http://www.ronsmachiningservice.net...op/gm-8-2-bop-auburn-posi-lsd-elite-gear-pkg/ Here is the Eaton Posi and gear package, http://www.ronsmachiningservice.net...bop/gm-8-2-bop-eaton-posi-lsd-elite-gear-pkg/
I always use Yukon gears.... Just do not want to spend time playing around tweaking a inferior gear set any more at 50+ years old...been doing this for 30 years now and I am even thinning out the used herd of rears. I build the Moser housings 12 bolt and just almost use the same shimming every time...It is nice less labor more money in the pocket. Jim