Dart says its As-Cast heads are "...for the commodity kind of guy, who wants to make between 500 and 800 hp, depending on displacement or power adder." The two new heads are known as the 170 As-Cast ...

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 ...

Good cylinder heads are necessary to the production of serious horsepower, but what exactly constitutes a "good" cylinder head? Typically, we identify them with big, impressive flow numbers.

Horse Sense: For about a year after Trick Flow stopped offering the original Street Heat cylinder heads, they were still available from Wil-Burt, the company that cast the heads for Trick Flow before ...