Ok I have a few questions. Been doing some searching/reading on the site. I have a 1989 Iroc. 5,7 TPI. J65,GH3,G80,MX0( 4 wheel disc,2.77 gears,limited slip,4speed auto w/OD) Looking in through the rear wheels,it looks like I have the PBR aluminum calipers(they have the fins on 'em). According to this site,my car should have a BW nine bolt rear with this gear ratio,engine and trans combo. It has a 10 bolt. I thought only the BW nine bolts came with the PBR calipers. I physically haven't removed the rear wheel to measure the rotor size to confirm. Also when I did the rear brakes the caliper didn"t require that it be "screwed in" to compress it,just a clamp. I bought the car from the second owner(car had 12,000 miles on it from 1st owner, traded in, bought by second owner in 1991 and I bought it from him with 78,000 last year) Am I misinformed about these rears and brakes or am I just reading everything wrong. Could this rear have been installed inplace of a BW 9-bolt later in its life? Also how would I go about upgrading the front brake to a "hub"( no castle nuts,cotter pins and packing bearings) design with better(bigger) calipers and rotors.Where can I purchase the parts. I'm running the stock 2 stripe 16" Iroc wheels all around.

 

Any one? I've done searching and maybe I'm just reading too much into it and confusing myself. Just need alittle clarification. Thanks!

 

with a 2.77 ratio then you have 9 bolt with pbr, 10 bolts have pbrs too, but i believe only on 90-92, not sure if any 89 had them and no pbr was available before 89.

 

i just did a LS1 break swap on the front with parts supplied by Ebmiller on the boards. hes a great guy to deal with and his prices are real fair. check out my cardomain for pics from the swap. its pretty straight forward.
matt