SR Boost problem spuddering

[s13dan]

I have a Redtop with stock T25,370cc injectors.intake FMIC, i had the boost stock for a long time then i turn the boost up with a Manual turbo XS boost controller i couldnt run more than 10psi as normal , then i got a new fuel pump... problem is i dunno what fuel pump i have.... i was told it was for a 300zx TT then he said it was actully for a 3rd gen RX-7.. then pump is a lot better than my stock one..i dont have the power elay thing.. im not really sure what that is. its brand new i got it from a autoparts store... FREE. its a carter P72165.. sometime i can run 14 psi with no problem but it does spike really bad.. but after the engine warms up it wont run more than about 11psi with spuddering BAD... real odd thing is that even when i was running 12-13psi when its wasnt spuddering the car wasnt any fast at all... HELP!?!