th400 upshifting problems

[prost67]

I got a rebuild kit from Jakesperformance and followed his posts on nastyz28 and a transgo 400 1-2 kit and a rebuild manual. I rebuilt the trans and put the sprag in wrong. I only drove the car 2 blocks and 4 shifts. tore the trans apart inspected everything put the sprag in right and reassembled. The trans will shift when first driving but when it gets hot it won't shift in drive or manually. If in drive and I rev the motor to about 5000 and let off the gas it goes into freewheeling till I rev the motor to 3500-4000 then the trans starts to pull again. I've been emailing Jake and have gone through the gov and made sure that was ok, the mod is new, Vac is about 8in. at 850 rpm in drive and 10-11 in. in neutral peaks 15-16 when cruising in drive. I've had the valve body off 4 times I did find some nicks in the transgo 1-2 valve and it did stick when fully pushed against the spring pressure. I cleaned the 1-2 valve and bore reinstalled and no change. Saturday I took the car out no change let the car sit for 3 hours at my house and drove it back to my garage and it wouldn't shift. This morning I took the car out drove it till it got hot and wouldn't shift then pulled the VB within 10 minutes of shutting the motor off and hot to check the valves and they all move freely. I took the VB apart cleaned ,checked for flat and reassembled per Jake's instructions and no change. it'll shift till it gets hot and when it does shift it feels really good, no slip or hezitation. As I said to Jake today I've done everything to the VB,gov, mod to make sure they are working right.

Thanks for any ideas.
Rick