i happen to be at the junkyard the same day they put out a posi 9inch rear, with disc brakes. i took it of a firebird, and plan to put it on a IROC z CONVERTIBLE. my question is will it fit? how do i know the ratio? should i do the swap? how can i find out if it is a good rear end? thanks alot guys! i always thought 9 inch rears were ford, but i saw it on a firebird??

 

There should be a stamp on one of the axle housings

 

How much did they charge you for it? Did they even know what it was?

If it came off of a 82 to 02 Camaro, it will fit the Firebird and vice versa. However if it came from a 93 to 02 Camaro or Firebird it will be and inch or 2 wider than the 82 to 92 axle but will still work.

If it really is a Ford 9 inch then it was most likely built by Currie or Moser, and is an aftermarket rear end, and I would jump on it especially if it was cheap.

 

i got the rear end for 80-90 $$$ i forgot exactly, it was a while back. it isnt in the best shape, it has some surface rust, but i will begin to work on it. my question really is, is it worth investing the money in? thats why i wanted to know the ratio, what kind, and know to check if its a good rear end?

 

HELL YES ITS WORTH IT!! lol!!

You stole it for $90.00. Especially if its a Curry or Moser.

It probably already has a 3 series gear and a posi.

The only way I could see it having an open diff is if it was fabbed at home by a home mechanic and no posi installed, or it was removed before it was junked and a stock open third member installed.

If it really is a 9 inch, just take the bolts out and pull the third member out the front of the housing. Count the teeth and you will have your gear ratio.

As for if it is a posi or not, I don't know much about Ford and identifying thier posi units. I would probably myself end up doing the shade tree deal of locking one hub in place and putting a torqwhench on the other.