Hi,

So I have a 545 stroker ( new build) in my 78 F150 4x4. just installed a TCI Maximizer trans, with a TCI saturday night special torque converter. it seems to be shifting way too early. from a stop, it seems to be short shifting immediately into second, and then 3rd at around 20mph. the truck doesn't really make its power until 3,000 rpm to 5,000 rpm. can I adjust the shift points for 1st, 2nd to a higher rpm using the vacuum regulator on the C6? i have not really tried full throttle launches, but at half throttle shifts come way to soon. thanks for the help.

 

Yes adjusting the modulator will change the part throttle shift points but will not change full throttle shifts. Also make sure the vacuum line is hooked up to full vacuum not ported.

 

I woudl also call TCI tech support.

 

That might need some mods; my 545 did. As you tighten the adjusting screw in the modulator the shift points should increase, if your modulator isn't adjustable, reinstall it in the trash an and install a adjustable modulator. That big inch engine probably develops a lot of vacuum so correctly modulating that trans is going to be difficult. I bet if that valve body was modified for higher horsepower, the line pressure might be too high, allowing the line pressure to overcome the governor.