I have a 1983 firebird s/e. Its not a trans am. I have a 2.8 v6 and its one of the worst motors made it has had 3 of them. I am currently looking for a new engine. i want to put a 350 small block in it. then i realized i could go with a 6 since i dont have loads of money to spend on gas. I have a chance to put a 4.3 liter v6 in there. someone told me that the t5 transmission will bolt up to it and that it should work out fine. the t5 came from the camaro i believe. Does anyone here know if that will work? or if a 350 will even drop in? or does anyone have any advice to what engine i should put in there. Im just looking for a reliable car that will run a long time, not a race car.

4.3L is the v-8 pattern

90 degree

the 3.8 is the 60 degree like the 4 cylinder

you would need a v-8 bellhousing

and then a complete exhaust system
and so on

the s/e was more "plushy" than the t/a

i had an 84 one
i junked it

was also 3.8L and t-5

it had perfect mint tan interior but no one wanted any of it

you could buy a reliable complete car for less than what youre gonna put into it converting it to a 4.3 or v-8

youd even be better off buying a factory v-8 f body thats needing another v-8 or something else done to it to make it run and drive again


these days its just not worth spending all the extra $ when parts cars are getting hard to find and good runnning cheap cars are out there still

it takes alot more $ and effort and time to do this then ppl think or plan for,

ive bene doing it for years and i finally quit and wish i had alot sooner,

they go to the shredder now


good luck

S/E's have a 2.8 Liter 60 degree V6.

Not a 3.8.

Don't they call the 4.3 the chopped-off Small Block?

I liked that motor... in my Blazer. If you wanted something peppy and efficient, I'd recommend the 3800. That's yet another great motor. Higher RPM range maybe (guessing).

This is more appropriate for the Engine swap section of this site, so I am moving it there.

However, my .02, go with a V-8 if you are going to go with a 4.3, same amount of work but the V-8 will have a lot more gains.

Your best bet, really, is a 3.4 V6 (this is a 60 degree, and from the same family as the 2.8) from a 4th gen f-body or you can still buy the 3.4HT replacement S-10 engine. All of your original 2.8 accessories, Intake, carb, distributor, etc, will bolt on with no mods. You just need the 3.4 flywheel with it. You will also need a universal low pressure electric fuel pump as the 3.4 has no provision for a mechanical pump.

There are some guys here who have done it with great results. I did an older carb 2.8 swap and used a 3.1 from my 90 firebird, also with outstanding results. If you use an 87 or newer 2.8/3.1/3.4 you can expect well over 200k miles and dead on reliability. I have done it and others have as well. Since you don't have an engine yet, the 3.4 is the biggest available that is a drop in replacement.

The 3.8/3800 Buick (GM Powertrain) engines require serious mods to install. The 4.3 will require everything that a V8 swap will require. Only the 2.8/3.1/3.4 rear wheel drive engines will swap in easily.

Hope this helps.

I would go even farther and say the 4.3 swap is one of the hardest, as nothing is available for mounting it into the chassis.

I like the 3800's, My 89 VN Commodore has one in it.
I hit 5,000RPM+ dayly and its pushing 330,000K (205,000mile) i give it a service every 4 months with oil designed for a turbo engine (better for higher heat/stres apps) and it runs smooth with no smoke but the 700R4 behind it is starting to fail.

The car only cost me $1,000 almost 2 years ago and the last owner used it as a burnout car (prob why the diff clunks) but other than the trans i havent had a problem with it.

They are deff a great engine, there are a fue other VN's around my area one has 410,987k on the original 3800 but the trans got a rebuild last year.