Alan, remember the same thing happening when the first good 'Stud-Girdles' came out or when Chev. went to 7/16 push-rods? After all the 'Monkey-Motion' was taken out of the valve system, the profiles had to be redone to achieve the same flow as the 'Floating' valves were flowing. As Abraham Lincoln said in that famous Tweet, "Them Harmonics is WEIRD'...!!!"