[Adger Smith]

I went from a tricked out lite weight 1.98 PG to a 2.12/1.35/1 Proflite and picked up almost .15...
That was with a 660 HP 425 LB ft tq V-6 in a 3200 lb car. The 60 was .02 better, but the middle of the track was where it picked up. The combination liked the second gear ratio. One time I did a back to back with a tricked out lite weight 1.98 vs a 1.76 and the car lost a full .10 with the 1.76. I'm like Jim, what you gain or lose all depends on the combination you have.
Weight, HP, Tq and rpm range vs gear ratios & Tq converter play a part.
Another thing I found was the more low gear you change to the more it tightens your converter stall. So the ideal converter for a PG may not do so good in a low gear 3 speed.