Overdrive Transmission - Mopar Overdrive Conversion Kit
Here's a look at an original, aluminum-case Chrysler OD four-speed. Note that the bolt-on shift arm for the 3-4 shift rod points down (pen) versus the upward orientation of the two other shift arms. Chrysler's original overdrive tactic employed this inverted shift arm, a redesigned 3-4 shift rod, and a new 0.76 Third gearset (from 1.39) to trick the transmission into OD status. The original Fourth gear remained at 1:1 but now was positioned in the shift quadrant where Third gear would normally be. Unfortunately, Chrysler's budget strategy included an undercut main shaft to suit the new Third gearset that limits reliability to the 300hp level. Passon's custom gearsets retain fullsize main-shaft diameters and sidestep this issue. View Related Article
|
|