I recently purchased an 86 iroc. I am going to swapping in an 01 LS 6.0 with 4L80e. I am going to be turbocharging it and hope to be sitting around 600hp. My concern is the rear end. It will be a street car with a pass or three at the track. What should I be thinking about doing to or with the rear end? Thank you so much guys.

 

Ditching the stock rear and putting in a Ford 9" or built GM 12 bolt.

 

Thank you so much,

 

Ford 9". Several aftermarket manufacturers build direct-bolt-in 9" housings for 3rd gens; most of them will also supply whatever gearing and axle spline you choose along with your choice of limited-slip/locker/etc.

 

The 12-bolt is a better fit to the vehicle in many ways. Also consumes less HP. If you don't need the "quick change" advantage that the 9" gives, the 12-bolt is probably the better way to go. Has to be aftermarket of course, same as a 9" in that regard; there's no stock 12-bolt that will work in our cars.

Expect the 80E to be a major ordeal.

 

Uh oh, what can I expect?

 

The trans tunnel is likely to need some enlargement, or massaging with a BFH at the very least.. The 4l80e is quite large.

 

Yup... doesn't fit our chassis without some significant custom body work to the tunnel. You'll also need a crossmember. And of course a properly set up ECM or stand-alone controller.

Altogether, not a trivial swap. Good transmission and all that; but a long way from a bolt-in.