Long drawn out story but the short version is:
I swapped my 60E to an 80E. Both 2WD. My original OS did not support an 80E. I did a segment swap from another OS. My 1-2 up shift is ridiculous. It will break the tires loose at 10mph and cause people to spill their drinks. I have replaced the valve body in the trans with one setup by a trans builder I trust (Finish Line Transmission). I double checked the 2nd VSS to make sure it was wired to the PCM correctly. The trans has an updated TransGo HD shift kit, drilled to the middle setting. It also slams into 4th at part throttle sometimes.
I have adjusted all the tables I understand with no luck. The very first shift in the morning is perfect when the trans is cold. After it has made a few shifts, it’s hard as hell. This leads me to think it has something to do with the transmission fluid temp tables. I don’t know enough about what drives final transmission line pressure to know what I’m doing. Any help is appreciated. My current tune is attached.
Been dealing with this for about 3 years and enough is enough….
Would swapping to a custom OS solve this? How do I do that?
Chris

 

I cant help much but my 80E has always had a harsher 1-2 shift. Its all stock with a little pressure bump.

 

can't see efi at work, but did you slow the shifts down (shift speed table), decrease the pressure at lower tq, and I am sure there are tables in there for temp differences as well.

 

the 3-4 was harsh in my stock 80 with a shift kit. When i put it back in the truck i was told to put the stock 3-4 accumlator spring back in to solve that problem..

1-2 was just a slight tuning and got it to where i liked it.