Pontiac 350 Or Chevy 350

[21_Phoenix]

I'm looking to improve my cars engine performance.
It currently has a 1970 Pontiac 350 engine in it

I don't mind having it rebuilt but from what I've seen online there isn't much horsepower to begin with.

Would it be better suited to switch the engine out for a maybe 80's or later 350?

I want to do the work myself.
just want to know which one will show more power with minimal work such as just replacing parts (camshaft, carburetor, etc)

 

[melsg5]

if you have a Pontiac 350 why not a 400 or 455?

 

[Kraig1957]

You could add a performance intake manifold, like an Edelbrock Performer 2156, and add a performance 4 BBL Carburetor (a 600 cfm will work well with the 350 to 455 cubic inch engine for a steet car). If you have single exhaust, you can change it to dual exhaust. If you still don't like the performance of the 1970 350 you can up the size to a 400 or a 455 and reuse all the performance parts. The Edelbrock performance parts will fit all the Pontiac V8 engines from 1965 on up.

 

[cammerjeff]

Something else to look at is what rear gear does you car have? Many cars made in the 1976 to around 1987 had ridiculously high rear gear ratio's 2.42 to 1 in was not uncommon. This was done in an attempt to get better MPG, but caused the cars to accelerate very slowly.
After you get the car running better, investigate the rear axle ratio, just swapping out the gear ratio to something more performance minded in the 3.23 to 3.55 range will really improve the acceleration of the car, it may or may not hurt the city MPG, but will hurt the Highway MPG some.
When I was your age I had a 1976 Grand Prix as a daily driver, Pontiac 350 2bbl Powered, I swapped in a 4bbl intake and carb, headers duel exhaust, recurved the HEI ignition timing, everything helped some, but when I swapped out the stock 2.72 rear axle to a 3.55 posi, the car came to life! Still not a dragster as it weighed about 1000lbs more than your Phoenix but at least it could beat my sisters 1974 Firebird Esprit powered by a 400 4bbl Pontiac V8.