Just for an RPM example my son was having a shift issue last Sunday at Keystone with his air shifter so he lowered his shift RPM from 6600 rpm to 6400 rpm on his stock stock 360, at 3200 pounds, 727 transmission, and 4.10 gears and in 90 degree plus heat it slowed from a 6.62 to a 6.64

1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time