Supercharger fuel question....

Can't say for certain, but with your 255 pump and 42lb inectors, I'm surprised you still have a stock regulator. I'd considered trying the stock unit at first with my Powerdyne but at the last minute I swapped it out for an adjustable unit instead.

There are basically two ways that you can adjust your fuel for boost: Mechanically or Electrinically. If you have the means to adjust your fuel curve electronically then most times, your stock fuel pressure regulator will be adequate (assuming your injectors are large enough for your application). The other way is mechanically. An adjustable fuel pressure regulator can help lean or richen the mixture across the entire RPM
range and make up for deficiencies in the computer's tune or inadequacies in injector size. Of course, the mechanical option is not going to be as precise as computer tuning across the entire RPM range. If you're getting a custom tune or have an EEC tuner of some sort and your injectors are large enough, then you really don't require an AFPR.

You're already pretty familiar with my current combo. I'm still using my stock regulator but have mechanically tuned through an adjustable FMU and the Boost-a-pump. Once the conversion over to mass air and 42s is complete, I'll still be using my stock regulator and tuning through the TwEECer.

Yes the stock fuel pressure regulator will increase fuel pressure with boost. But I have no idea how that will be indexed. It could be .5 psi per lb of boost, it could be 10 psi per lb. I have no idea. I also don't know how much psi that diaphram will withstand. I don't think you'd blow it out with the air pressure, but if fuel pressure goes up at a higher rate than the air pressure does, than the fuel may blow it out.

I think I'm going to do some testing, and just put a fuel pressure guage on, put a pressure pump to the stock pressure regulator and see how fuel pressure responds to air pressure.
I'm curious