ok simple question i have 1990 iroc with stock rear with 3:23 gears in it and rear disc brakes and it just blew out on me, i am going to buy a rear out of a 1988 iroc with rear disc brakes and a borg warner with 3:42 gears and i am just wonderin if i will run into any trouble trying to put this in or if there is anything i should know before hand
i really dont know much about the borg warner rears ether so info about them would be nice and $250 that seems more than fair to me what do you guys think?

 

Your 90 IROC may well have 11.7" rotors with alum PBR calipers. The 88 will have 10.5 rotors and Delco-Moraine iron calipers, which aren't very desireable. You could, however, swap the brakes from the 90 to the 88 with the correct backing plate. For info about that, check the following link:

https://www.thirdgen.org/forums/faq-...iscs-89-a.html

Check the following link for info on the 9-bolt:

https://www.thirdgen.org/forums/faq-...now-about.html

JamesC

 

I though the 9-bolt had 3.47 or some othe 'odd' ratio..

 

Borg Warner 9-bolt has a 3.45 gear and is good and strong. My 9-bolt with 3.70's has held up fine behind my 383 for over three years now on the street and strip.