the power boost valve fits in the vacuum line for the FPR a bit like a bleed valve for a turbo it restricts the vac to the FPR giving a higher fuel line pressure
vocky has shown that fitting the vacuum line to the inlet manifold instead of the intake pipe the fuel pressure in the rail rises but then after the ecu learns this new fueling it compensates for it
the only real way to adjust the fuel rail pressure is to bypass the stock FPR and fit an aftermarket FPR like an FSE adjustable FPR
but you will then suffer the ecu's learning curve even with higher fuel line pressure it will just spray for a shorter time on the injectors
you can run a higher fuel rail pressure no problem this will give a better misting from the injectors and less duty cycle but you could probably do just as well by putting in some forte specialist injector cleaner in your tank 🙂
imo unless your running silly bhp and are running lean then no point in a uprated fuel pump only other reason i can think to change to an uprated one would be the OE pump is old and sluggish and its most likely cheaper to fit the uprated one over another OE one
as for a remap i've not had mine done yet as there are just not enuff mod done to my engine to warrant the 4bhp a remap would give
i would need tubular manifold ported head, cams and a lightened flywheel just to get a good boost from the remap 🙂
but still its up to you what you do🙂 im not trying to stop you just think working solely on the fuel supply is not the best way to get performance from a z22se 🙂
