I have a 1990 GTA for my project car........well it used to be a GTA. My whole objective with this car was to make it a showcar with *****. I also wanted it to have something different about it. With my personal love for 3rd gens and this being my car since I was 18 I started the "re-do" process. I ripped out the motor and basically saved the block and built a monster of a 383. Haven't had it dyno'd yet but i figure it at about 550-600hp. Pulled out all the electronics in the whole car, and now running it with a carburator. Of course you know this also leaves me to re-doing the whole dash cluster too. (looking forward to that). Although many has said it was a bad idea getting rid of the fuel injection, I love the simplicity of it. That and it is soooooooooooo neat looking under the hood without wires running everywhere. Now the motor is in and running great and I had the whole engine compartment re-done, ripped out the heat/ac, relocated the battery so there are less visible wires, had the firewall smoothed and of course had it painted yada yada yada. Now I am moving into the chassis. I have a few questions about that and what seems to be a problem for everyone with the 3rd or 4th gen. Camaro/Firebird........................the exhaust. Here is what I am thinking:

For the trans I think I am going to keep the 700r4 but have it overhauled. I am told with the right parts it will have no problems handling the HP. What do you think? Do you know of a shop with a good reputation?

The rear is tough because I will be street driving it 90% of the time. I was thinking of the 9" but realistically I am not going to be towing it to the track every weekend so do I really need all that? Do you think the 12 bolt will be enough? I like the price alot better.

I started looking at the BMR suspension and it "looks" great. Will my car "hook" when I want it too??? Dont get me wrong I will run the car on occasion...lol

Now the exhaust!!!!!!!!!!! Damn this underbody!!!!!!!! I am not going to run cats. I hear mufflex makes a system to go from the collectors on long tube hookers into a 3.5in Y then back in the muffler with the 4"........ single out. Do you think the mufflex system will give me enough flow? Will I lose HP? I am open to suggestions and sound clips would help if anyone has similar amount of HP. God true duals would be sweet. I almost considered going to a 4-link just to get 2 pipes over the rear.

 

As far as the rear goes, a 12 bolt should be more than adequate for the motor you've got. It's not far behind the 9" at all in terms of strength.