Ok guys this is a little into the future but I wanted to ask ahead of time

Im gonna put a grand national motor into a 3rd gen trans am or firebird etc

my question is this

I know obviously the rears on the trans ams are probably alot more built then that of the firebird

but I was thinking of getting a firebird, cause it would have alot less options (save weight) the sway would be about the same and it will save me more on car insurance

now heres the questions, do any firebirds have rears like the formulas etc? i.e. stronger?
I aso read too they have different axle splines, are any beefed up
basically what I want is the rear and drivetrain from a formual in a firebird
without swapping is it possible from the factory?

and do they have the baffled gas tanks?
or should I just suck it up and get a formula instead?


I already have a GN motor, built billet trans with converter and aluminum driveshaft

 

The rear in a trans am is no stronger than the rear in any other thirdgen. The only way to really get a stronger rear would be to get one from a TTA car, which just isnt gonna happen. Now, you could look for the later years 89-92 IIRC had 28 spline axles instead of 26.

 

rears - you can look for a 9 bolt, strongest factory rear for these cars.

also your GN will be a tough fit as the TTA which used a similar motor to the GN used different heads (lesaber I believe) to fit in the engine bay as we have less room then G-bodies.

Also baffled tanks cam about in the 89+ cars IIRC.

also which ever trans you install, if it isn't from a thirdgen (sounds like it) then you need a cross member setup for the torque arm (I believe Spohn sponsor above) has them

 

The strongest rear for these cars IMO is the 9 bolt, which is what came in TTA's and other performance models(like my 89 GTA).

I've gone 11.99@113 w/1.63 60ft on my old stock TTA(now sold)and the stock rear held up, though I dont know how much longer it would have.

If it were me, I'd look for a better rear like the Dana 44 at least or better yet a 12 bolt/9 inch. Oh and you might want to consider getting a stronger driveshaft if you plan on racing the car much, I snapped two alum shafts at the line and had to get towed home both times I would have saved alot of money if I would have gotten the moly shaft I have now the first time around.

HTH,
Steve

 

hey thanks alot bud

yeah I actually do have a TTA right now, however the reason I wanted to do the swap was to sell the TTA
it deserves a better home for someone collecting it, I bought it for all out performance, however when I thought about it, a hard top car with almost no options should be able to get farther then the TTA since it has T-tops and leather interior and power everything almost

thank you very much for your ideas
where did you get the shaft
and what rear are you running now?

by the way I have the same name on turbobuick.com

 

Cool, I have the same name over there too - usually I'm in the TTA section(obviously)though I've been kinda absent lately

Anyway, I got my driveshaft from the driveshaft shop which is not that far from me on Long Island. They have a website http://www.driveshaftshop.com/ but it might be better if you can find a more local shop to make one if you go that route in case there are fitment issues or what not.

For a rear I've been running a Moser 12 Bolt that has 3.42 gears in it this year and I was running 3.08's in it for 2002-2003. So far it's held up great, I dont know exactly how many passes I've put on it but the number is probrobly over 1000(I compete in regular points series)with a best 60ft on 1.47 and most of my 60fts last year were 1.4's. This year and 2002 I ran it on pumpgas and the 60fts have been all mid 1.5's with no problems. IMO it's a good solid rear, though a little expensive to buy new.

I hear ya on the whole racing a TTA thing, it's why I sold the stocker I was racing(though I held on to my other bone stock cars). It went 11's so fast and stock that I knew if I were to go further I'd need to cage it, and thats something I didnt want to do.

 

Looks like Steve beat me to this thread

 

Thats a first, I was wondering where you were

 

hahaha