I have an 89 IROC with Disks in the rear (BW 9 Bolt). What 10 bolts can I swap under it? What year cars? Does it matter if it is Disk or Drum? Are any years more desireable than others? TIA

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Black 89 IROC...Mods: 355, 10.5:1 comp, Big Solid Crower Cam, TFS heads, Victor Jr, Holley, and a 5 spd...

 

Yes, you want a 90-92 10-bolt, they have the better disc brakes, and the 28 spline axles, like your 89 does. Its a direct swap if you get one with the same or close gear ratio as you have now.

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TTT

 

What, I didnt answer your questions?

 

I think he meant other cars that can interchange. Answer = none, except a fourth gen, but it's 4 inches wider. You'll have to find another thirdgen rear if you want an exact fit. Some 89's and 90-92's are better because of the stronger 28 spline axles. As for the brakes, I'm not sure. There's another post about this here - https://www.thirdgen.org/messgboard/...ML/001391.html

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