converter locking/unlocking issues

[slowlsx]

Just purchased this turbo 408 nova and I am having issues with the original tune that's in it. Once I get to 55mph+ the converter will lock but its seems if I try to level off at let's say 65mph the converter will unlock unless I give it a little more throttle.

Could this be because the hi/low TPS numbers are too high? The motor is a 408 with almost 11:1 compression and small cam so I'm guessing it has plenty torque to not need much tps % for it to cruise at a steady speed.

Should I 0 all that out or cut it in half?

Attaching the two images

[Keithbilello]

In minimum throttle release set both low speed tps and high speed tps to 0. All 4 of them.

[chevypower101]

I would also check your 3>4 shift id compare both that and the torque converter lock up speeds and make sure lock up speeds are a little higher for corresponding throttle position cells. If everything looks fine id up the minimum tcc cycle to like 50-90 on the whole board most people do 90 min and 100 max but the higher the numbers the more you will feel it like its shifting another gear when it locks in