Your MPH matches up pretty well with ET and 60'. I would try 18lbs and do a short-ish 2nd gear burnout in the water box. You may see a small improvement, but the MPH says it won't be much.
My carburetor is too big and my heads are too small. The plugs indicate a lean condition. I will go up one size on the primaries, set the pressure at 18 and hold on. :-)
