We had heard good things about Trick Flow Specialties 23-degree aluminum heads. If the claim was true that we could expect serious horsepower gains over stock heads and even some aftermarket cast-iron ...

The breakthrough of the 11R 227—a tip of the hat to the cylinder head’s 11-degree valve angle and fully CNC’d 227cc intake ports—is less revolutionary than evolutionary. It takes lessons learned from ...

If you're a company that makes aftermarket cylinder heads for Detroit's most recent powerhouses, you've found yourself in a bit of a pickle in recent years, as mass flow rates for ordinary ...