C6 vacuum modulator question

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mustangandy

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My Car
1971 Cobra Jet 429 Ram Air C6 auto 3.50 traction loc
[url=https://ibb.co/Wtx4kTW][img]https://i.ibb.co/dgWwPh0/mine1.jpg[/img][/url]
I'm installing a Transgo 67 -1&2 shift kit into the C6 of my 429CJ. Thought I might as well replace the vac modulator too as no idea how long its been on the car. I got the scott drake c4az-7a377b one which has a white stripe. The old one has a white stripe too but strangely no little adjustment screw at the hose end. The pin is 1.654" which I believe is the standard length?

I'd like to raise the shift points ie raise the revs at which the box changes from 1 to 2 and then from 2 to 3 (as its in 3rd by 25mph). From what I've read turning that little screw clockwise (so inward) will help do this? So how many turns should I go? I've read anywhere from 2 to 10 turns for effect?

The other thing is the pin length. Again, I've read that a longer pin will help with a bit more performance shifting? Anything from 1.677" to 1.75"?

Can anyone put me straight on this please?

Cheers

 
The modulator adjustment and pin length do change part throttle up shifts, as does manifold vacuum. However, at WOT the governor determines shift points. Unfortunately, there are no "kits" to change Ford governors as there are for GM transmissions. They have to be adjusted by changing weights and springs. There are a few small companies that have done the experimentation to come up with "combinations" that work. Chuck

 
The modulator adjustment and pin length do change part throttle up shifts, as does manifold vacuum. However, at WOT the governor determines shift points. Unfortunately, there are no "kits" to change Ford governors as there are for GM transmissions. They have to be adjusted by changing weights and springs. There are a few small companies that have done the experimentation to come up with "combinations" that work. Chuck
Thanks Chuck. Yes I thought that the shift kit and vac mods won't make a significant difference but, coupled with replacing the shifter and linkage bushings etc hopefully I'll end up with a better shifting experience :)

 
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