Well there is a RPM limiter placed on the EFI mustangs. That is set on the computer by the factory about 6,450 RPM. ALthough there are aftermarket chips that can reset the upper RPM limit or eliminate the limit. Most stock EFI AOD stangs shift any where from 5,200 up to about 5,400. If a car is modified it can shift upwards of that. If you have the modifications you build the RPM range to suit what you have.
Good Luck
