I don't think its the fuel pump. I was leary of the fuel pump too but it flows PLENTY of fuel under boost. IT really sounds like a TPS sensor or another sensor that is was going out before the turbo. There is someone else with the HRC kit complaining about the same thing, laggy before boost abd such. I know the TPS sensors are really senstive, specially if any water gets in them. Once in a whil mine acts the same way, I shoul dhave my datalogger when I get home so I'll know more then.
Wyatt Leras
http://www.turbogs.dsmpower.com
98 Eclipse GS Star Stage 5,000 Turbo kit