Chevy 283 swap with Pontiac 350

[KarbonXIII]

I just got word of a Pontiac 350 engine that a guy has in his 70 lemans apparently a fresh rebuilt (he restores cars probably going to get him to do my car). Anyways he wants between 5-8 hundred for it and i'm wondering if the 350 is worth it.

Granted its going into a 71 T-37, and my #8 cylinder the piston rings are shot and its going through oil.

I really do like the way that my 283 sounds, wondering how much different its going to sound with the 350 in it.

[Scrapper]

i had a 283 with 350 heads on it but you can get some good sound out of a 350 with exhaust system.

[KarbonXIII]

Right now I have cherry bombs on my exhaust but the whole exhaust needs to be replaced.

Is the sound going to be that much different. I dont like that really steely sound to the exhaust where it almost sounds like its choking.
Though that might be headers lol.

[Scrapper]

you could put cherry bombs back on it. theres a site that you can hear what exhaust sounds like idleing,drive by,and fast sound. i cant remeber where i found it might have been summit or jegs. you could put on it or orange peelers or your cherry bombs witch are the same. you just don't want that turbo sound right?

[KarbonXIII]

Yeah i think so, the sharp clacking sound instead of the low mean rumble

[MrPbody]

350 Pontiac bears no resemblance to 350 Chevy. Zero parts interchange.

350 Pontiac, rebuilt, is worth $800. (a quality rebuild costs about $2,500, not including block and heads)

350 Pontiac is torquey and durable. In stock or mildly modified form, a good choice. If you want more horsepower, not a good choice. 350 Chevy has significantly more potential, but less low-speed power. In a heavy car that doesn't have high performance requirements, 350 Pontiac is probably a better choice.

The Pontiac does not "bolt right in" where the Chevy is. The wiring is different, as the starter is on the opposite side. Fuel line and motor mounts are also diferent, both on the block and the frame.

The upside of the change would be, if you DO put the 350 Pontiac in there, down the road, 400 or 455 will bolt right in. Except at the highest levels, 350 Chevy is no match for 400 Pontiac.

Jim

[KarbonXIII]

wow. something to think about I guess. I dont think i'll be going to a 400 its not a race car for me. This is my only car.

[MrPbody]

Actually, a 400 Pontiac can be made to get excellent fuel economy and still pump out some respectable power. The key to fuel economy with a V8 is low-end power. That is, the engine makes power at lower RPM than other engines. This is where Pontiacs SHINE!

But I understand, it's a big job to change it all.

If you're looking for good street manners and some power when you "kick it", a properly prepared 350 Chevy can be great. You'll need to listen to someone outside the street hot rod or "racing" scene, as Chevy small block engines built for horsepower are hurtin' for torque and vice versa. An "RV" cam, Edelbrock Performer intake, well-built Q-Jet carb, small headers, all make for a very good low-speed engine.

JIm

[KarbonXIII]

How come Pontiac 350's are so much less powerful than Chevy's?
hope that doesnt sound like a stupid question.

I really dont feel like I can classify my car as a muscle car with the current 283 under the hood. lol guess i'm looking for something that i can spin out my tires, have a little fun, show off here and there lol

[MrPbody]

There are a lot of factors involved regarding a given engine's ability to make power. The main "drawback" to the 350 Pontiac is the relatively small bore diameter. It prevents the "good" heads from really flowing up to their capability, as much of the in-rushing "mixture" will ram into the cylinder wall. "Unshrouding" the valves is the term. There simply isn't enough "room" to do it with a 3 7/8" bore, where the heads work VERY well with the 4 1/8" bore found in the 400.

On the good side, 350 Pontiac is very "snappy" and makes good torque. It's well suited for a daily driver, especially in a car weighing 3,500 lbs. Tough stuff, too.

A minimum of 396 CI would be necessary to call the LeMans a "muscle car". 400 Pontiac would be more appropriate in the Pontiac body, but there are many out there with BBC transplanted.

Jim