Well, here is my take. Today I installed my dads HPP on level 3 which is the 90HP setting. From a stand still full throttle run w/o the T/H the shifts were....soft?? With the T/H on the shifts were firm and it rifled through the gears. I think the reason being that when engaged the T/C is locked in all gears instead of 3-4-5 without the T/H on.
Hey I'm no expert by far but I think someone else will chime in.
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