Packard Forum Index » V-8 (1955-56)

Recall that the Twin Ultramatic is designed to downshift (kickdown) to first under full throttle at speeds up to about 60 MPH, for passing. However, this behavior is often undesirable to today's owners.

The purpose of this kit is to make it "harder" for the transmission to kickdown, by changing the shift lever geometry so that the throttle pressure is not raised as high at full throttle. (Kickdown occurs roughly at maximum throttle pressure.) At the same time, the throttle pressure is raised on the low end, resulting in a firmer shift. Installation instructions are below.

I am planning on reproducing the shift extension kits. They will be made as shown below, from carbon steel. I am targeting a price of $11; please let me know if you are interested.