Originally Posted by Aaron
EC is right. Port volume really doesn't matter, it's the minimum cross sectional area of the intake port matched to the engine displacement and max engine speed.
that's all relative. Port volume requirement is directly tied to engine size and rpm range. A 500-550 CID engine (i.e aftermarket Pontiac IA or MR-1) isn't going to have a small volume port. Look around at what the fastest cars are running for port volume now.
in the old days a fully ported Pontiac iron head had maybe 190-225 cc's
now everyone is banging on 300 cc's or larger
small block Chevys, circle track/drag racing, have 290 cc intake port, splayed valve heads, for only 350-400 CID
GM Splayed Valve
- Product Specifications -
Head Name: Splayed Valve
Engine Type: SB Chevy 358" - 400"
Applications: Drag Racing, Oval Track
Bore Diameter: 0
Intake Valve Diameter: 2.23
Exhaust Valve Diameter: 1.55
Chamber Volume: 45cc
Intake Port Volume: 288cc
if they are using 288 cc heads for a small block 350 CID Chevy, think what a 500 CID Pontiac needs
certainly not the same exact port volume, for an extra 150 CID, unless the engine is being revved a lot lower