Highest flowing sbm heads?

And proving it. For decades. That’s why two heads can flow say…300 CFM and one kicks the **** out of the other.

There is way more to making horsepower than just flow. Port shape is just as important (maybe more so) than flow.

How the port flows in reverse is just as important as how it flows in its normal direction


ET tells the story and I’m not the only one writing the book. Take those leaky azz W5 heads and plant tomatoes in them.