I think that there might also be some influence from your cam and your computer.
Your cam will kick in at a certain RPM and your computer will also "stop" the emissions equipment at open throttle. I noticed that with my chip my car hits the "point" before 2500 RPM.
Someone else may be able to explain this better, I'm kinda shooting from the hip.
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Driving: 1998 F-150
Far way in Edmonton==>
1995 Mustang GT