Hey, I just joined this site in hopes to get a question answered. I have a 1987 Pontiac Firebird with a 2.8L V-6. I want to, eventually, upgrade this to a larger, more powerful engine, the 305 or the 350...which is better?
Regardless of which V-8 i choose, I'm sure it is a pretty involved project. What all needs to be done to this transformation?....I've read that the tranny with my 2.8Lwill bolt to a larger V-8, but that does not sound right. So if you could, please help me out with what I should do to get this running stronger. The more detail the better, or if they even make a book / manual for this sort of this, it would greatly help. Thanks.

I just did it to my car, the trans wont work. Theres a sticky at the top of the page that explains alot. Give it a try and see if it answers all your questions.

Good luck and post any other Q's

thanks...figured...
since you just did it, could you tell me about how much $$ it was, and what all you ended up doing?
--also, did you go FI or carb?

Well heres a short break down


I got a GREAT deal on a 90 tpi motor with trans $300

I sold the TPI unit and ecm for basically what i paid for the motor and trans.

I bought a mallory adjustable fuel pressure regulator for $80
(you need this to drop the pressure down to a level a carb can handle if you keep the in tank fi pump)

Edelbrock performer rmp manifold from a friend for $50

HEI dist from a friend of a friend $20

Accel wires and coil $90

Motor mounts $20

Oil, plugs, Antifreeze, throttle bracket, Alt from junk yard with bracket, vaccume line, gas line, clamps, misc crap you forget till your into the swap $200

v8 Y pipe $80

Im sure theres some crap im forgetting but this is a basic list of what i had to get.
The motor mounts were the hardest part btw.

Also i had a v8 rad given to me , you can use the v6 one UNLESS it has hoses on the same side as the v8 rad

Carb v8 swap is WAY easier but keep in mond emiss testing !!

thnx a bunch
I'm gunna try and find a donor car ... probably do what you did and go carb......pending on how courageous i feel.

Oh and the carb, you'll need one of those of course, i forgot about that!

Im just about finishing it all up now, getting the exhaust hooked back up and all.

Was it worth it? HELL YEAH! Just the feeling that you did it when you get in and turn the key and feel the difference between the little v6 starting and the v8 starting is unexplainable. I sat in my car for like 30 mins today with the motor idling!

Good luck with it.


Also , some say you need to change the front springs, i did not do this, my car sits about 1/2 inch lower but it doesnt seem to be any worse then before. If it does cause a problem ill change em later.

I swapped to a 327 carb and ripped out damn near every electrical wire under the hood and my ecm. One of the best days of my life. Here in Idaho theres no emissions testing

Some other things you'll have to worry about are is your hood going to fit and what are you going to do for exhaust

When I bought my car it had drop spindles installed in it already and now with the V8 in it, if there is a 1/2in groove or anything in the road it scrapes big time. I'm going to have to put the original spindles back in and probably sell the drop spindles in the classifieds or something.

If you have emissions inspections, you'd be best advised to get a complete V8 donor car and swap over everything associated with the engine. Although 87's were offered with a carb, it was a computer controlled version, and you can't legally put a non-computer controlled carb on any US 3rd-gen that's driven on public highways and by-ways. It's federal law, although enforcement is typically local (there is the guy who imported a 20+ year old car from Canada, but he's the exception, not the rule).

WOULD THERE HAPPEN TO BE ANY LITERATURE ON THIS??

On what? The v6 to v8 swap or the emissions crap?

The v6 to v8 swap info can be found all over this site from old posts and members who have done it . (mine is finally complete!)

As far as emissions goes, I dont know about where you live but here theres always someone who will throw stickers on for you or someone who has stickers.

If you have emissions testing or inspection in your area, be a responsible citizen - keep it above board and do it right. Ever wonder why performance enthusiasts have a bad reputation among the masses (especially those in positions of authority)?

Contact your local department of motor vehicles to find out what will be required in your area.