I rebuilt it a few months ago and it seems to be a little sluggish in 1st gear as if it’s slipping. All other gears pull/shift as they should but starting off just isn’t the same as it was. I’ve pulled it back out 3 different times chasing other issues and rechecked all clearances (all to factory specifications).

So far Parts replaced:
All steels and frictions
Seals
Plastic accumulators upgraded to aluminum
Molded pistons
Low roller clutch (sprag)
Forward sprag
Torque converter
Input drum (27 spline)
Bushings
Pump body and cover (complete) including 13 vein rotor and slide
Boost valve (stock new)
Transgo drop-in Pressure regulator valve
3rd gear check ball capsule (servo bore)
Rebuilt valve body

Line pressure:
60-65 at idle
Pressure boost at shift is approx 180-190
After shift approx 90 then dropping to 60psi
Reverse 90-120
Sharp spike with throttle blip in gear 60-120

All specs are verified through the ATSG book.
Any ideas on why it’s acting like this? I was kinda thinking it was a bad torque converter but reverse is as normal as it was before…I’m at a loss…..