convertor trouble??help

[dimeforce]

This is going to be long, sorry.

I have been running real good couple of months ago. 5.50's at 128.
The truck got loose on me in the finals when I hit high gear and lifted and saved it. I took the truck back the next week and it won't get out of its own way. I went from 1.31 60ft to 1.49 and lost 8-10mph.

It is hard to get the motor to come up on the brake and feels like it is pulling 2 trucks behind me untill about 6800rpms then it wants to fly but I shift at 7400.

I pulled the trans and convertor, went in the trans to check stuff and everything looks good.(powerglide with brake) I checked the stator support and front pump, support has not turned. Sent the convertor off and they made it spragless.(said it had slipped some). Put it all back together and still the same thing.

Compression test shows good, no blowby.
Checked valve springs, they were a-bit weak so I replaced them, still the same thing. Pulled the carb apart twice, found nothing still the same thing.
Put a new coil and wires, didn't help. Put a new digital 6 and didn't help.

What can I have possibly missed?

[Hutch]

If you are sure the stator tube did not spin , the only thing left is a motor issue.
Converters are torque sensitive and low power=low stall.
Run the car and make sure that the converter doesn't get really hot and the trans is still cold if this is the case you will know if your stator tube has spun as the flow back to the cooler/ trans gets cut off.
After that im not sure what direction to send you in, boost level, ign timing etc.

Take care ,Hutch