[67vertBird]

Currently have a pegleg 2.9x rear (67 code XD) and want to get a posi, and taller gears. It's an auto with 350-400 HP. What options do I have for a simple swap? Varied street/hwy driving.

[67vertBird]

Currently have a pegleg 2.9x rear (67 code XD) and want to get a posi, and taller gears. It's an auto with 350-400 HP. What options do I have for a simple swap? Varied street/hwy driving.

[jwcfbd]

you could just buy a new posi carrier and gears. This would be the cheapest way or you could go all out and get a whole rearend. It all depends on you. Gears will cost about $650 and a new rear end is about $2000 give or take.

[RicksGTO]

If you want to swap rear ends, might call Gary Parker in Plano as he has built rear ends for a lot of people in this area. I'm pretty sure he has a 1st gen firebird rear end now that he would build with the carrier and gears of your choice. He built my 8.5 and does good work. His numbers are 972-578-0012 or 214-274-2623.

[sdbob]

Think about a later 8.5" rear.Parts are plentiful.Check prices on both.I am working on my 67, found a 3.73 posi complete for 400$ out of a 75 F body.Had to move the spring perches the rear is ,I forget now I think it is less than 1/2" wider per side.I didn't want to destroy the original 4:33 rear.Good luck

[78taman]

I have a rear end to fit your car, it is an 8.5. The only thing you have to do is shorten the driveshaft 1 inch. Thank's Rick for the recommendation.

[gjn]

Use the following formula to figure out what gears you want:

RPM X Tire Diameter/RE Ratio*336

I ran 3.70s with a 26 inch tire for a while; however, only being able to do 63 at 3k rpms drove me nuts. I dropped to 3.25's and am much happier doing 71 at 3k. I live in Kansas City where you can't get any where without jumping on the freeways.

[67vertBird]

78taman, are you the one in Plano? If so email me [email protected] and we can go over it.
Thanks
John