RE: P80 starting problems
A couple years ago, I got a dozen or so "bad" pumps from JetCat and tested them on a P-80. About half would stop accelerating the engine in the 30-45K rpm range, as I stated above, and fail to complete the start. Some of the rest wouldn't get the engine to max rpm.
Looking at everything else said, my best suggestion is to replace the pump. You are basically just barely (or not) staying ahead of the required acceleration ramp. Increasing the gas % is one I hadn't thought of and maybe that will keep you in business for awhile. 2.5v max pump isn't bad at all.