1978 318 heads? Small port? Or large

johnnymac2k6 said

so to throw some fuel on the fire...Why do manifold companies market the intakes like this ? 318-340-360? is it just assumed the port mismatch isn't That bad?

http://professional-products.com/in...lock-mopar-v8-crosswind-intake-manifold-satin

i have a used one of these lying around...

Click to expand...

The port size is nice if you can match it, but not necessary. The engine will run either way, but it will just sacrifice a few horsepower.

The manifolds will physically fit, so they can market them for all of the small blocks.

If you really want to port match, and have mis-matched head and intake, you can always get a carbide burr and gasket match them. Problem solved....