I just swapped in a 70-72 C4 transmission into my 73 Ford F100. Under normal driving conditions it shifts from 1-2 at 10mph and 2-3 at 20mph. If I lay into it a little harder it delays quite a bit longer. But I want it to be delayed longer at normal driving.
Is there a different modulator I can get(this one has the screw in type)? How long can I make the modulator pin?

Will installing a Transgo reprogramming kit change anything?
Thanks.

 

Anybody? Wondering what the Transgo 40-2 kit is like in the c4.

 

On C6's, the black coded modulator gives the latest/highest-rpm shifts, but I don't know if the same color codes apply to C4 modulators.

 

Max pin length is 1.677.

 

Bump! I just order the 40-2 Transgo kit from summit along with new C4 filter. I'm interested to hear experiences with this kit. My C4 runs pretty good, but father has said he noticed some slipping (not much detail provided). I haven't driven more than 30 or so miles at a time or driven it that hard as I'm trying to restore it a little at a time. Not sure the last time tranny fluid was changed so I'm gonna do that and figured I would throw in the Transgo kit too. Any thoughts on this kit?