what does a stock FPR do when it sees boost?

[b18a1+gsr-trans]

i am wondering this cause i am going to make a change with no extra tuning, will it disproportionately raise fuel pressure with boost or will it just act like it does at WOT NA? (42psi)

i have been running it connected to the manifold since i started driving it boosted, if i disconnect it and throw in a 50 psi regulator (no vacuum line) am i loosing or gaining fuel pressure at full boost?

The idea is to produce 43.5 psi of differential pressure. So if you add 10 psi of boost then that's pushing back against the injector so you need 53.5psi of fuel to have the same flow as no boost. Disconnecting the vacuum line will run your car rich at idle (since it won't be 43.5 minus the vacuum) and leaner under boost since it won't be increasing the FPR to match. Stock honda FPR's work reasonably well under boost and there isn't usually a need to upgrade them.

-Michael

[b18a1+gsr-trans]

so i when im at 11psi my regulator is already regulating at 54.5psi?
i didn't know a stock regulator had a 1:1 boost to fuel pressure..
awesome, one less thing to screw with :lol:

thanks

[HBoy]

Most (if not all) stock FPR are 1:1.