Before the port and polish, left, and after, right. Most of the metal was removed from the area on either side of the valve stem casting.

by Mike Palmer

Conventional wisdom has it that if you want more power from an engine, you have to add more stuff, such as higher compression pistons or a turbocharger. But suppose I said you could get more power by removing stuff? Further, what if your engine would be more reliable if that same stuff were removed? Sounds like a late-night cable infomercial, right? Eat all you want and still lose weight.

While it’s true that I watch too many infomercials, it’s also true that by surgically removing a miniscule amount of aluminum from the intake port of a cylinder, you can gain 4 horsepower from that same cylinder. That’s at least 16…