Cylinder head porting is one of those garage mods that lives somewhere between speed-shop legend and flow-bench science. Also referred to as port and polish, the idea is simple: Open up the intake and ...

In the Feb. '11 issue ofHPP, we presented the new Edelbrock Performer D-Port head in the article D-Port Development. At the time, the head wasn't production ready, so our story was written based on ...

The E/I column represents the exhaust-to-intake flow relationship expressed as a percentage. Stock intake valve length is 5.244; this head uses 5.350, or 0.106 inch longer Stock exhaust valve length ...