I'm looking for information on swapping a disc brake rear end from a 1986 IROC into a 91 camaro rs. I need info on the proportioning valve, parking brake setup,etc.. I would appreciate any info or a link to some info.

 

Waste of time & effort installing those POS rear brakes. Better options out there.

 

What's the gear ratio in the Iroc rearend?

 

The IROC rear is a 3.23 POSI. I wanted to put the rearend into my 91 rs convertible because i have a complete 86 IROC donor car with a damaged body.The RS has a 2.73 rear w/drums.

 

With the recall kit installed (if it isn't already), the rear discs on the 86 will work fine--and will provide a better ratio and limited slip. The disc rear would also allow easier upgrades, as DJP suggests, such as the following:

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

JamesC

 

I wouldn't waste your time on the old calipers and just upgrade to PBRs right off the bat, you won't be sorry.

Ed

 

I know that there are better options out there, but I have a 86 IROC w/complete rolling chassis for a donor. I want to replce the 2.73/drum rearend in my 91 RS with the 3.23/disc rearend out of the IROC.Basically what i'm asking is what other parts do i need off of the IROC to make my brake system work correctly with the IROC rearend installed on the 91 RS.

 

We didn't do much to answer your question, did we? Check the following link for master cylinder info:

https://www.thirdgen.org/forums/susp...fferences.html

Because I'm ****, I'd replace the M/C and proportioning (combo) valve. The emergency brake cables will be different. Maybe someone else will chip in here, as IIRC, the emergency brake attachment in the tunnel is somehow different. Also, if you plan, at some point, on upgrading, keep the pieces you remove from the 91.

JamesC

 

As James stated, now we get it. You'll need the whole rear, the e-brake cables, and the master and prop...and I strongly suggest at least rebuilding the rear calipers or you'll see no drastic improvement. You may have an issue with the e-brake cables as your '91's adjuster is different than the one on the '86. Good luck!

Ed