904 MAINSHAFT

Our 904 mainshaft allows you to change 1st gear ratios in the 901 and 911 gearboxes. The stock mainshaft has 1st gear machined on the shaft; the 904 mainshaft has a splined removeable 1st gear.

Porsche designed this mainshaft for easy ratio changes in their race car geaboxes (first used in the 904 race car, this shaft was also used in the 906, 911 and 914 racers).