[chiphead]

Yeah, that cam is WAY too much for the displacement and compression.

What you do with the engine's setup depends on how much money you want to dump into it. The cheapest way to address this is to use a summit 2801, or a similar cam with 205-218 intake duration and 112 LSA. Maybe even drop back to the 2800 since compression is so low. The earlier intake closing will build some vacuum and the wider LSA will smooth the idle some and broaden the powerband. The power output will be low because of the low compression. I figure 300-325 HP at 4800 RPM is doable if you leave the heads alone.

The proper way to "fix" this is to pull the heads and figure out what is really going on. CC the heads, figure out the deck height and verify piston valve reliefs. The either mill the heads to reduce chamber size or sell them and buy a set of heads that will boost compression properly. Ideal compression for a motor like this would be 9-9.5:1. Combine that with a properly set up HEI and a custom built Quadrajet carb. That'll give 375-400 horses but not be so tune-sensitive that it blows up at the first tuning mistake or batch of bad gas. It'll have a stable idle, run cool, not load up and die in traffic, make power right above idle and make enough vacuum for power brakes. That's what we call "good street manners".

Its really sad that so many guys come here on PY with engines that are mismatched like this. Poorly running, weak engines with no throttle response and bad street manners. And then we've got to be the bearer of bad news and tell them to tear their new engine apart to fix it. I'm not bashing the OP, I feel bad for him. He's got this engine that should be pretty strong, but whoever chose that top-end package really screwed the pooch.

This happens way too often, and I'm sure the regulars here have seen their share of it in person. Where are all of these mis-matched engines coming from? And it's not just pontiacs. I can't tell you how many "muscle car" engines I've seen where somebody used forged pistons, good internals but used low compression smogger heads, a cam that is WAAAAYYY too big, and then top it with that AFB-style Edelbrock carb that doesn't work for crap. I guess I shouldn't be surprised but I am. *rant off*