[Steve C.]

Stated- "the advertised #'s are just that...advertising."

There is more to the seat duration than advertising.

One example:

http://www.wallaceracing.com/overlap-calc.php

Also.....

"When comparing two different cams, if both profiles rate the advertised duration at the same lift, the cam with the shorter advertised duration in comparison to the 0.050 duration has more aggressive ramp. Providing it maintains stable valve motion, the aggressive profile yields better vacuum, increased responsiveness, a broader torque range, and other driveability improvements because it effectively has the opening and closing points of a smaller cam combined with the area under the lift curve of a larger cam."
Billy Godbold at Competition Cams


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