Transmition guru needed

[64moneypit]

My 64 stang has a c-4 tranny that was drag raced probably a shift kit too. one of the reasons I needed to rebuild the engine. the guy that sold it to the guy I bought it from swappe dout his high performance heads back to stocks and left a hot cam in it...by by valves and head gaskets....
my issue with the trany is the quarter stick shifter makes life interesting but can deal with it, and more importantly the manner in which it shifts.
if you put it in drive and try to go the thing shifts into 2nd at 5mph (maybe 3 seconds after gas) and into drive at around 10-15mph. if you shift it like a stick it shifts nice and hard depending on how hard I push it chirps the tires when shifting. how can I make the auto feature shift in a more proper manner.
someone said that there may be a screw in the vacuum modulator on the trany or that a push rod in the modulator needs to be eithor lengthened or shortened to change the timing? or do I need a different shift kit or rebuild?

thanks
andy

 

[rbohm]

most modulator valves are adjustable, but you need the one with a single vacuum nipple on it. the screw is in the nipple. you need a small screwdriver to make the adjustment. if you set the screw about halfway in its travel, that will get you close to the proper adjustment, and you can play with it from there. in delays the shift and out makes it shift sooner. be aware that sometimes there is little room to adjust the modulator in the car, so you may need to pull the valve when you adjust it, so have a pan available to catch the trans fluid as it drips out the opening.

 

[65fastback2+2]

whats your rear gear???

 

[64moneypit]

rear gear? as far as I know its a stock 8" rear. only way to know is open up the diff and count teeth right?
ithe modulator is on the top passenger side of the tranny right?

 

[USU_Stang]

rear gear? as far as I know its a stock 8" rear. only way to know is open up the diff and count teeth right?
ithe modulator is on the top passenger side of the tranny right?

there should be a little plate riveted to your differential which has it's size, gear ratio and casting numbers. This is no guarantee that the gears haven't been changed, but is still a good indication.