s12 in a lotus 7 kit car

[graememk]

well the s12 is in the mk indy replica lotus 7 and the engine running megasquirt but i have a problem, the cars been on the rollers today and its running full fuel but it goes lean above 3800rpm the injecters cant supply enough fuel with the amount of boost (8psi), what do i need to do, as far as i can see its either fit new injectors, change the fuel reg or up the pump, what have others done that run high bhp please

graeme