Since I'm posting....
Guy at RS said he swapped a wally255 for the jay racing 340 and it made nearly no difference...this was not on the dyno when the swap occurred, but who knows. He also said it is nearly silent, which is kinda cool. End conclusion was that the pump wasn't getting enough voltage/amperage and needed to be rewired....might as well do a BAP at that point? IDK...
http://forums.evolutionm.net/alterna...fuel-pump.html
Also another guy with the jay racing pump, 1g dsm, said to make sure its rewired...
http://www.dsmtuners.com/forums/dyno...#post152424157
Searching around