Hi, I have little experience with posi rear ends. I wanted to find the right rear end drum to drum but haven't been able to locate one. I am considering buying an 8.2 posi unit for my 65 Gs. It apparently came out of a 67 GS Any difference? Also, I have a .273 open now Any changeover difficulties/issues/tips? What is a 28 spline bolt on axle? What is meant by 4 pin? Thanks, Steve
The strongest 8.2 BOP factory posi units are 4 pinion (4 spider gear) type 1st used by Pontiac division in '66. Olds def received these in '66 for HD applications, & I would assume Buick did as well. The 4 pinion units are much stronger than previous & later 8.2 2 pinion offerings. A factory 4 pinion posi is a closed clamshell affair with no large windows like the 2 pinion units. Only one small window is in the side of the carrier, it is rectangular in shape aprox the size of a Zippo lighter. There were different ratios of the Pontiac 4 pinion Safe-T-Tracks & one needs to be careful when ID'ng as to get the proper ratio carrier. Pontiac & BOP 8.2's use the following ratio carriers: High ratio... 2.56, 2.78 Mid ratio... 2.93, 3.08, 3.23 LOW ratio... 3.36, 3.55, 3.90, 4.10, 4.33, & old aftermarket 4.56, 4.88, 5.14, 5.57 Spline count, refers to the number of "teeth" or splines on the end of the axle. While some axles may be very similiar in diameter, & have the same number of splines, they will not interchange. An example, is trying to slide an 8.5 corporate 28 spline axle into a oem 28 spline side gear in a '64-67 BOP 8.2 or '68-72 Pontiac 8.2 rearend. The 28 spline 8.5 axle, will not fit in the "BOP or Pontiac" 8.2 side gear. '67 8.2 BOP "posi" carrier should set up fine in a '65 Buick 8.2 rear. Just make sure the carrier is the right ratio for the gears you intend on running. :3gears: Roger
Wow!! Thanks for the one stop info shop. Concise clear and with examples! I really appreciate it. Steve
