forum.jdrace.com

I am in the process of planning my 8.2 to 8.5 swap in my 71' GTO. Doing this swap means I will have to shorten my driveshaft to work with the 8.5 rear.
One of the questions I had was how to adapt my old driveshaft (or a donor,as in my case) to the different pinion yoke on the 8.5. The original pinion yoke on the 8.2 took a u-joint around 3.5" wide,the 8.5 takes one around 3 7/8" wide. I found out they make a u-joint just for this situation. I never heard this mentioned in all the reading I had done on the internet,so figured maybe it would be useful info to have if someone else is doing this swap.
http://shop.advanceautoparts.com/webapp ... GRPUCVSAMS____

That would be the one... also called precision 372 and spicer 5-3022x (i think) I will check that spicer number. JIm

Now on the Goat we have to double check the drive shaft u-joint cap diameter.... Some where I heard the BOP drive shafts used larger bearing caps in the drive shaft .... On the chevy they are 1 1/16" caps I think the BOP (including GTO) have 1 1/8" caps...So this joint may or may not work for you. The larger wide cross shaft will fit the 8.5 yoke for sure. Double check that as I wil ltoo. Jim