Where to set kickdown linkage?

[waynejody]

I have a 1970 Challenger 383 with 727 automatic tranny.
I need to know at what speed the kickdown linkage will properly kick in.Right now from a stand start it will shift from 1st to 2nd at 30-32 second to third around 45.
I have a 78 warlock it shifts 1-2 at 40 and 2-3 at 70, why so much difference?

[70gtx]

you should set by how many rpm's you want to shift at. if the cars have different gears in the rearends that would make a difference in speed it shifts.

[mauve66]

From a standing start your shift point will vary by how hard your into the throttle. If you are looking for acceleration only, you don't want it shifting before your specified RPM, and at half throttle you want it to atleast get up through at least half of the power curve. The linkage is threaded and you can adjust it each way for your needs. First check that you actually have full opening of the carb with the pedal floored then set the linkage