Help me to understand cc's of heads.Would going with bigger cc make more power?Right now building a 383 w/ F1 Have some Pro1 64.Would there be any benifit by going over to some 72cc heads?

 

Generally speaking (and in your given example), more cc= less compression = less power NA. AFAIK, the reason forced induction motors run lower CR is due to the extra volume the TC/SC adds to the intake.

Off the top of my head, you need to add in some factors here to determine your overall power level:
CR with pistons (flat, dome, dish), to include
Has the block been decked?
Have the heads been milled?
Have the chambers been cc'd?
Proper pistons for rod length (5.665, 5.7, 6.0, etc.)?
Amount of boost you are going to run (from experience, the pulley boost # is a guide, the more air you flow- better cam, heads, etc. the lower your boost will be, I got 2 PSI out of an 8# pulley P600B on my 383, and on the first run with a 12# pulley I got 6 PSI).

Sounds like you have good parts with the heads & blower you mentioned. How about the bottom end? Forged crank? 4 bolt mains? H beam rods?

 

The general logic is that you can run more boost with lower compression, resulting in more total power.

There are some technical reasons as to why lower compression should make more power with a SC engine also. The extra total cylinder plus chamber volume gives you more volume to fill with pressurized air, so more power. Also, assuming the same peak firing pressure, the pressure will stay higher in the cylinder later in the power stroke resulting in more power.

Mike

 

Hey thanks for the reply fellas.The reason I asked is that right I have the pro 1 64 cc heads w/215 runners.But was wondering will the 72 cc make more power?Right now I have the 15 psi pulley.But will increase boost as more mods are made.As for the bottom end all forged intenals with h beam 6.00 rods and J E inverted dome pistons.and the comp cam that everyone suggests.