IMO you need to replace the entire fuel system from the tank to the injectors. I agree with other that 42#'ers are not enough. Fifteen pounds of turbo boost on a 351W is going to make ALLOT of hp. I bet with a good tune you'll make over 600 rwhp and 600+ rwtq. That kind of power will show you allot of weak links in the drive train/rear suspension. It should be a scary fast ride once you get it up and running.
Originally posted by 1000HP Preston: How much RWHP from a turbo car will that fuel system support?
A Stage 2 fuel system is capable of supporting 800HP from a forced induction car. You can easily upgrade the pump to an Eliminator or Pro Series pump to bring it over the 1000HP mark. The Stage 3 will support about 1000HP.