Does anyone here have any info on a rear end swap from a 86 IROC to a 91 camaro RS? I am swapping a 3.23/disc brake rear from a 86 IROC into a 91 RS convertible with a 2.73/drum rearend. I'm having trouble finding info on what parts i will need such as proportioning valve, parking brake, etc... I have a 1986 IROC donor car with a complete rear end & brake assy.

 

Anyone?

 

If the 86 Iroc parts car you have is the same car you took the rearend out of, you'll need to use the proportioning valve from it on your RS. The e-brake cables that are already on the 86 rearend should hook up and work fine on your other car. That's really about it. The 88 and older style disc rears require a different proportioning valve when switching from a drum rear. On the 89 and newer disc rears, you can still run the drum brake prop. valve since the smaller PBR aluminum calipers require about the same fluid volume as the drum brake wheel cylinders. The 88 and older cast iron calipers take a lot more fluid volume than the drum brakes to work properly. Oh yeah, I almost forgot to mention that the thread pitch is different on the 86 prop. valve compared to your 91, so you'll probably have to swap the hard brake lines from the 86 to your car as well. I can't remember if that applies to both front lines and the rear one, or if it's just the front lines. The thread pitch on the prop. valves changed from 1.0 to 1.5 around 1990.

 

thanx for the info.