To which of the two heads are you referring? If you are talking about the Speedmaster factory CNC ported head, I will agree with you that they are unimpressive. 200cc port, 93% throat and 266 cfm peak on my bench. They are almost forcing you to install a larger valve. If you are referring to the non ported Speedmaster head, I'd love to hear more. By the way, the port I am currently working with (on the non CNC head) has the valves sunk 0.090" and 50 degree seats.