I have a 1989 IROC-Z with a 9-bolt borg and warner on it. I was planning on building up a 10-bolt for it. But what i want to know is if the rear discs from the 9-bolt will bolt directly to the 10-bolt.
thankx

 

As long as the 10 bolt is an 89+ disc rear, or else you'll have to change the backing plates.

 

Ok, so whats involved in replacing the backing plates if a disc brake 10-bolt is not available.

 

We did that w/ my 89 IROC. It involves drilling new holes for the caliper mount bolts on the ends of the 10-bolt housing that is to be put in. After this, you will then need to space out the caliper mounts as needed so the discs fit in the caliper properly. For more in depth instructions, email TPI Guy, he did most of the work on it.

 

If it's a disc rear, you'll have to drill as mentioned. If it's a disc rear, you should be able to just pull the axles, unbolt the backing plates, and bolt the new ones on.

Don't forget that you'll have to re-shim your caliper carriers in any case.