[KoolBRZ]

I just got back from the beach. Tried 2 tunes on the way out, weak power, 28 mpg. made a new tune while I was there, good power, good AT shifting in "D" mode, mpg went from 28 to 31 as we went down the coast from 20 mph to 60 mph. Power was just about a perfect match with the transmission. Refilled in Salem and drove 75 mph north, which usually gets about 30 mpg, this time got 33. PI was off at 75 mph, (2600 rpms) with loads from .5 to .7, but back on with loads up to .8 or .9. See pic below, 36 is the tune I ran today, 37 is the one I'm trying out tomorrow. Will it get better mpg with PI on at 75 mph? Or does it get better mpg with PI off at cruising speed?