M21 in our cars with the RPM and torque band peak/usable 1000 to 1500 rpm lower than a Chevy. M21 was 3.90 or 4.33 only. Pontiac engineers knew far better than Chevy what they were doing and were leaps and bounds ahead...
Si Vis Pacem Parabellum
1967 Starlight black PMD Engineering 400 Auto 1968 Alpine Blue 400 4 speed 1968 Verdoro Green 400 HO 4 speed 2013 1LE 2SS/RS Inferno Orange Camaro.
