Engine/Transmission Swap
Asked by rkybronc Jun 03, 2013 at 06:48 PM about the 1984 Pontiac Firebird SE
Question type: Car Customization
I have a 1984 Pontiac Firebird S/E with a V6, Rochester 2 barrel Varajet Carb and the
700r4 stock automatic transmission. I was given a 1968 Pontiac 350 engine with a
Rochester 2 barrel Varajet Carb that I plan on rebuilding as it has sat for 7 years.
Can I put the 350 into the 84? Will I need new motor mounts and a new tranny? If so,
what tranny would go with it? Turbo 350? Turbo 400?
6 Answers
If you are just rebuilding to stock the 700r4 will be fine and should bolt right up, there is also a kit that costs about $125 to rebuild the transmission, it has a larger servo for the band and a Kevlar band, I think the kit gives the trans a disability rating of 500 hp. Worth looking into, the 700r4 was used on "PRETTY MUCH" all rear wheel drive GM vehicles up to the early 90s. That was capitalized and quoted because it wasn't used in all rwd vehicles just most.
Can I put a 350 engine in a 1984 Trans Am from a GMC Vandura van
Coltonandkelsey answered 8 years ago
I'm trying to convert my 700r4 to a 350 turbo will I have to buy a new tail shaft and a different cross member or will the stock 84 trans am cross member work?
The Pontiac 350 is NOT a straight swap, The Firebird came with a CHEVY 305 and Chevy transmission. Pontiacs will NOT bolt to these. The exhaust is another issue. It will take some hunting to get the right fit manifolds. B4 that you have a mount issue. No Pontiac mounts exist as no Pontiac motor was ever offered in 3rd gen Firebirds. It CAN be done, but it take a accomplished mech. /builder.
You'll also have problems bolting a 700r4 to a Pontiac block. The transmission only has a Chevy bolt pattern, so you would need an adapter plate.
Can I put a 283 in a 1985 Trans Am to replace the 305 and can I use all the parts for it