Just installed new modulator valve in 1969 Cougar with FMX, 351W 4V. The modulator valve is blue stripe Standard TM10. From sitting in drive at stop sign then light pedal acceleration transmission shifts to 2nd at 10mph and shifts to third at 20mph. What is the most optimum shifting calibration of the modulator valve for power, fuel efficiency and health of transmission? Is this shifting sequence currently too fast? Thank You guys for all your recommendations
Depends on the rear axle ratio.
3:00 to 1
Sounds pretty normal.