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1980 Pontiac Trans Am Firebird ENGINE

Hi everybody, My name is Jovan and I got a 1980 Trans Am Firebird, The car has another engine(truck engine) V8, its ok but I would love to put in a car V8 engine that can go with my 80 trans am.

What kind of engine is best for my TA?? I heard a 340 Chevy motor is perfect but I dont know

Do you mean a 350 Chevy? A 340 is a Mopar motor. I’m not 100% sure, but I think the bolt patterns between Chevy and Pontiac motors may be different depending on the year of the car. You might still be able to do it with an adapter plate. Maybe someone else can comment on this.

I’d probably stick with one of the offered engines for that year. I think a 403 or 455 big-block would be a good choice for smoothness and performance if it will fit that year without modifying the subfame. Again, someone else more familiar with Pontiac’s lineup that year can probably answer that better… A 350 would probably be a good compromise between performance and economy if it will fit, and there are of course thousands of performance options for this extremely popular motor.

that car came with the 301 as base engine. there were some made with a 305 chevy motor and the turbo 301. i have even seen the wimpy 265ci motor mentioned but never seen one in person. what motor does your car have? i think you would have mentioned the turbo version.

Whatever engine choice you decide on…just avoid the 4.9 Turbocharged version. I owned one and it was a dog. I think most kids on a bicycle could out run it.

If ur lucky, u got 305. So easy to swap on some good heads, maybe 305 vortec and good cam and frame is setup for easy true dual exhaust piping. Fun project.

There weren’t too many choices for an engine in a 1980 Trans Am.

If you really do have a truck engine in there it is most likely some form of a small block Chevy.

It’s not always easy to tell one small block from another so there really is no telling what you have but if you’re really wanting to swap it out anyway then it really doesn’t matter.

As has been said, the bell housing pattern is different on a Chevy engine when compared to a Pontiac (or Oldsmobile or Buick) engine so unless you plan on swapping both engine and transmission then you need to made sure at least what make of engine you have in the car.

If it’s a Chevy engine and you want to swap then probably the easiest way to go is with a 350. You have many options from building your own to buying a new crate engine.

Don’t neglect the transmission while you’re in there. Adding major horsepower to a weak transmission just means you get to crawl under the car some more later.

I used to have a Turbo Trans Am. While I agree with missileman that in stock form it was pretty weak, the engine really responded to an aftermarket cam and light porting/polishing of the heads.

The 305 was a great engine for a boulevard cruiser. It would break the tires loose and pull out of a light ahead of most cars while not burning too much 87 octane. And parts were/are plentiful and cheap.

@Bisbonian…I never had time to upgrade the 4.9 engine. I swapped it to a neighbor for his 400 out of his '79 Trans Am and he took my turbocharged 4.9. I would have traded cars but his wife nixed that idea. She was okay with the engine swap though. I think I got the better end of the deal since the 400 would roast the rear tires in a heartbeat. I’m glad your aftermarket upgrade paid off though. I also agree with @RodKnox…a 305 would be a more sensible engine. Fuel economy is very important these days. I think my 400 go about 12 miles to the gallon if I was lucky.

Unless you live in an area that has mandatory smog inspections, I would suggest a Chevy 350 with a turbo 350, 400, or 725 transmission. There are plenty of parts available now and will probably be available far longer than for the lesser production engines.

This combination will give you the widest range of options from track only to boulevard cruiser.

What is your budget? That will be your biggest hurdle to climb.
If it’s cheap power, a Chevy 350 with a 700R transmission will probably be your best bet.
If it’s a one-off customization, fab up some parts and drop a 572ci engine in that bad boy

If you have a 301 (4.9L) and a “metric 200” transmission, I would avoid this combination like the plague. The 301 was one of GM’s worst motors, and it was paired with arguably the worst transmission they had at the time. If you want the car to be fun, quick, and reliable, I would put just about any engine/transmission combo in there other than that. If you’re going for a 305, there’s no reason not to go with a higher displacement motor. (like a 350) Your mileage will suffer more from your driving habits than the larger displacement motor. You should be able to get at least 15-18 MPG in city driving with a 350 if you keep your foot out of it some of the time.

With a T/A of that year, you can also look forward to sagging door hinges, weak rear springs, dash parts that fall off, door handles that break, water in the trunk, and a world of electrical gremlins, especially with lighting and accessories. Also, not recommended for any kind of winter driving.