You're shifting the lever before the RPMs max out, and it shifts later? Maybe a dumb question, but I have to ask, just to be clear.It may take some time for the transmission internals to move the fluid where it needs to be, at WOT with a manual shift.
See AlsoEverything You Need To Know About GM Automatic TransmissionsHow Do I Know What Type of Transmission I Have? - Mister TransmissionATI Powerglide - Superglide 4® Drag Racing TransmissionWhat is Chevy Turbo 350? - Cottman Transmission and Total Auto CareI do recall the "Dual Gate" Pontiacs. While I realize that this may be a different story, maybe it's related.
Just a thought, though I think I've experienced the same thing, and made the above assumption about shift delay based on a manual shift.
FWIW, I had a B&M built 350 trans in my '56 Chevy wagon with their "slap shifter", and when I hit the handle it shifted, now, leaving rubber, both upshifts. I didn't have a rev limiter, though...and I may have had it wound up a little above the preset governor shift RPMs, it being a 'Vette motor and all. :laugh:
