Automatic Transmission - how to control TC lockup??

i have a revmax convertor.sometimes i punch it WOT and it feels a bit slower,than other times.sometimes i punch it and its ALOT FASTER.i had a very relaiable rebuild 3 months ago.no issues with the tranny.i believe that my converter is locking up sometimes and other times its not.is there anyway to control this?should i get it retuned? TC and tranny are both new. 3600 Revmax. with an ACE racing tranny.it locks up normally on the highway at 60mph.feel like its got a 5th gear.im happy with it,except for this little problem.no check engine light.new solonoid maybe?

prob need a tune, but you should be able to feel if its locked up the way it drives
try and step on the brake lightly when it feels like its locked under power, see if it unlocks
with a higher stall, the throttle postion switch is seeing a diff postion at speed than before, input to the computer is diff-thats my guess anyway, lol

yes. i was thinking its probably in the tune also.so it should be faster unlocked?i think its weird that the problem is kinda intermittant.but yes i will get it tuned when my pocket book agrees with me.

I have a frost tune with the same set up you have. Ace 4l60 and revmax 3600 and mine locks up at 46 mph every time on the dot.