Hi, I have an 84 Z28 that I converted over to a th-350. At full throttle it shifts at about 3800 rpms, it should be shifting at about 5500. I just put in a new vaccuum modulator and I have it running off of a vaccuum plug in behind the carburetor on the intake manifold. I know that the vac modulator controls upshifts and the kickdown cable controls downshifts. My kickdown/detent/TV (whatever it is called) cable is not hooked up, I have a new bracket ordered for it that I am waiting for. Would this do it? I just put the tranny in, so I dont' know how it acted before. I also have a very large cam in the car, with about a 489 lift, and I the convertor stalls around 1800 rpms when the brake is held down and I give it gas. Any recommendations on how to get it to shift at higher points? Also, it WILL shift whenever I want it to if I do it manually, I just want it to shift normally when in drive. Thank you

 

bump

 

Install the Trans-Go Performance Shift kit & this will address the WOT low rpm upshift problem besides firming up 1-2 & 2-3 WOT shifts.

 

To change the WOT shift points you will need to recalibrate the Governor. B&M sells a nice kit just for that.