EZ-SPEC YOUR NEW FOUR-SPEED (OR MUNCIE GEARSET)

The gear that drives the speedometer is assembled on the mainshaft (output) and needs tailoring to your axle ratio and tire diameter. We'll do the math for you (no entry required).

Back in the day you could order almost anything that would bolt together and not every car was intended for the street; 'Numbers matching' doesn't always mean street drivable. For general use --- starting a car with a mild street motor and typical tires on a hill or parking garage ramp without slipping the clutch --- General Motors aimed for a total reduction of 9:1 (transmission first gear multiplied by the axle ratio). We'll use that and your application profile as a starting point and make the recommendation for you (no entry required).

Muncie four-speeds have a removable steel sleeve supporting low gear. Our gearboxes offer an improved version of General Motor's basic design or a roller bearing alternative. We recommend the bearing for all but cars seeing significant strip time --- it's mechanically more efficient. Dragsters want our improved sleeve because it puts more surface under the shock when launching the car (flattened rollers don't roll). We'll make the recommendation for you (no entry required).