Originally posted by techinspector1
I have a lot of respect for Streets, but in my opinion, for this combination, these heads will work fine. They'll flow all the air you need up to 4,500 rpm's and that's where the cam is gonna sign off anyway. THIS IS A LOW-RPM, EXTREME TORQUE COMBINATION. It will provide maximum grunt, smooth idle and excellent mileage on crap gas. If you want different characteristics, DO NOT USE THIS COMBINATION.

The small runners in these heads will keep mixture velocity up at lower rpm's and help to pack the cylinders for maximum power. You could increase the intake size to 1.94" if you want to spend the money, but I think your money would be better spent on doing some bowl work and a 5-angle valve job. Use new, STOCK Chevy springs. I think I'd use a stock cast iron Chevy 4-bbl intake manifold that was designed to accept a quadrajet instead of the Edelbrock unit. The runners on it will be slightly smaller and there again, the lower volume will contribute to higher velocity at lower rpm's. The Performer will work, but I think a stock intake would work a little better. It's all in the combination and getting all the parts to work together toward a common goal. I suspect that the exit port on the Performer is larger than the entry port on the heads and that will disrupt flow slightly. Perhaps the exit port on the cast iron unit more closely matches the head ports. It would be interesting to investigate this for yourself, don't you think? I think that with either manifold, I'd also use a four-hole phenolic spacer under the Quadrajet so the mixture could make the 90 degree turn out of the throttle bores into the intake runners more easily. DO NOT USE AN OPEN SPACER, USE A 4-HOLE. An open spacer effectively turns your 180 degree low-rpm intake manifold into a 360 degree, high rpm manifold. If I used any other cam for this combination, it would be a Comp Cams X4250H. I'd order the cam and lifter kit CL12-231-2 for $228.50.
I think your right, its kinda like running water thru a hose, the smaller the hose the faster the flow I remember Edelbrock having a manifold called SP2P, had a spread bore bolt pattern. Wouldn't work as a good torque manifold? If I remember it had small runners???

Alan