I need a new rear end for my 92 RS , its got the stock one in there now with is 10 bolt 2.73, with drum brakes. I saw an ad for a Borg Warner 3.43 out of an 89 IROC I know with the gear change my speedo will need to be calibrated, but will this be a direct bolt in from my other rear end?

 

If it has the same type of brakes (drum or disc) as your current rear then yes, it's a direct bolt in.

 

Should be a bolt-in no matter what brakes it has. If it's a disc rear you just have to use the disc e-brake cables.

 

damn, maybe it's called the brake balancer
you'll need to get that to go from drum to disc
in a drum car, its a 70/30 bias towards the front because discs stop you more than drums
the brake balancer makes it 50/50

 

Direct bolt in, just make sure you get the parking brake cables and proportioning valvle for that year. These items are different then what your 10-bolt drums use. Thats about it and a BW 9-bolt with the 3:45 gear/ limited slip and the 11.655 rotors & Alum PBR calpiers
is a great up grade. And the speedo gear is a minor item you can pick up at the dealer later. Made that swap on my car. If you want more info do a search, a ton of posts on that swap.