Right, I have a chance to get a 3rd gen rear axle 3.23:1 that has discs.
I have drums on mine and 2.72:1 so it would be a great swap.

However I have a posi and the axle with discs does not.


My car is an 88 5.0TPI IROC with the posi rear end and drums (from the factory).
The axle for sale is apparentley off an 86 Camaro (that's all the seller knows about it).


Will it all just work together so I end up with a posi and 3.23:1 and discs?

 

No unfortunately it won't.

Your 2.73 is a 2 series carrier, and the 3.23 is a 3 series. The ring gear will miss the pinion by about .300" .

You need a ring gear spacer. Then it will work.

You'll hate the 86 disk brakes. That's arguably among the worst brake systems GM ever put on their cars. They also won't work very well with the drum master cyl and proportioning valve; those calipers (cast-iron Saginaw) require those other parts to match them.

 

Well that ideas out of the window then...

Livingt in the UK is a PITA.
I want discs on the back and these cars are pretty rare over here so I can't just go looking in a scrap yard for an axle as there won't be a 3rd gen in there...

Back to the drawing board I guess!