I put an edelbrock rpm air gap on my car. And it runs as if it has a vacuum leak. I pluged off all vacuum outlets (pcv,brake booster, vac advance,tranny modulator) and it still runs like crap. I sprayed ether around the intake base and carb base hoping I could hear the car pick up rpm but no luck. So I though that it might be an internal vacuum leak. So take off the intake put new gaskets in. Put it all back together.......same thing.
It barley runs, idels at 1500rpm, shakes and runs rough but you rev it up and it smoothes out.

The block is a 69 4bolt block, forged crank. It has probably been rebuilt. So if they decked the block any amount would that cause problems in gasket sealing? would I need to get my intake planed? I took a edelbrock performer off so Ill put it back on and see if that makes a difference.

Digger

 

man, i just swapped my heads, and i have the SAME problem now.

itll run perfect for the first 15 mins i crank it it, after that the idle goes to RRrrRRrrrRRRRrrRRrrr and it damn near cuts off, and gets worse from there.

check your wires, ..see if they are going to the correct places...