The best( and about only) example of a P7 motor drag racing on this forum was my buddies 68 Dart he raced all summer, year before last.

68 Dart 3000 pounds with driver
904
Old busch restrictor plate motor. Small 248/258 roller cam, compression was at about 12 to 1.
He used old w2 2 inch headers he made work
4150 carb, forget how big.

Car went low 9.40's at 142-143 MPH, probably put 50-60 passes on it, then sold the motor to one guy, and the car to another.
So with probably not the " best" p7 motor to use, he still got it to fly.
With bigger cam and more compression i have no doubt it could have threatened the 8's. Those heads are just darn good.