Yeah you mentioned head flow in post #3 but I laser pointered the "murdered S.S." in post #12 only because I have first hand experience with them. I even drew a crude diagram. This is why W2's work so well! It isn't just because of the oval port and offset rockers. It's due in large part to the VERY tall S.S. It's so tall you have to reduce it for optimum low and high lift flow. Toot-toot. J.Rob