rear differential question

Does anyone know what type of rear end would come factory on an 86 Camaro IROC Z28? I thought they all came out with limited-slip diffs but I could be wrong. If they came out with something other than that is there a way I can find out what mine would have without taking it apart, like by the VIN or something?
My rear end right now only spins one tire when I push on the gas so I don't think that sounds like a lim-slip diff. It tics me off because it cuts down on traction and it looks sad to leave A BLACKMARK (instead of blackmarks). If you know what my problem could be just let me know. Thanks

i think it should either be a 7.5 or a 7.625" 10 bolt. or you could have a 9-bolt, sounds like you dont have a posi, but if you post a pic of your spid code sheet(in you center console) i can tell you exactly what its got

An '86 TPI should have had the Borg 9-bolt unless it was not ordered with rear discs. Count the bolts in the cover, or look for the rubber fill plug on the cover of the Borg axle.

i think it should either be a 7.5 or a 7.625" 10 bolt.

those two are the same thing

An '86 TPI should have had the Borg 9-bolt unless it was not ordered with rear discs.
I thought all third gen camaros came out with rear drums? Both third gens I owned had rear drum brakes and front discs.

nope, most iroc's and z28's had rear disk posi, with 3.42's

those two are the same thing
get over it ya dwarf

nope, most iroc's and z28's had rear disk posi, with 3.42's
Usually 305s with 3.42 and 350s with 3.23 - at least from what I've seen...

Posi, rear disks, dual cats, etc. typically came in a package option such as G92 (in 1991 for example).