Just put in a Racetronics FP and hotwire kit

[Beer99C5]

Just curious, car is still on jackstands but I fired it up...showing 70 PSI. I was expecting low to mid 60's. Is this par for the Racetronics Fuel Pump kit for the C-5's ???

Guessing I need to rescale the IFR chart to reflect the new pressure? (Looking around to if if Marcin is gonna slap the back of my head and say of course you need to rescale the IFR table LOL)

[TAQuickness]

Of course <slap> :D

That seems a bit high, but if it's consistant, you should scale for it.

[dfe1]

It may or may not be a problem, but excessively high fuel pressure can result in inconsistent injector operation. You're only up about 12 psi compared to stock pressure, so it probably won't be an issue, but if you run into something flaky that might be the reason. Some older style injectors don't have the "beans" to pull open against high system pressure.

[redhardsupra]

of course you need to rescale the IFR table
engaging unnecessairly slowly head slapping mechanism... ;)

yea you do need to redo your IFR. however you want to figure out how much fuel pressure you really need. no need to stress it if you dont need it.
fuel pumps are designed for certain voltage. if they want 12v and you'll give it 18v, it might run, but who knows for how long.

[FreddyG]

I have the RaceTronix fuel pump kit in mine along with a Boosta Pump and my fp is 70 lbs. at idle and drops 10-15 lbs. under boost. This is right along with your fuel pressure. Do you have a BAP on it or is that just the fuel pump giving you that fuel pressure?

By the way, I have 60 lbs. MotoTron injectors if that matters at all. :cheers:

[pkincy]

I would also suggest doing a first tune with 70 as the idle pressure, but you may find out as you drive it and monitor fuel pressure that it drops a bit at WOT.

Mine idles at 58 but will drop pretty quickly to 54-55 psi at tip in of wot and will drop further to to 52 psi on extended wot pulls.

So I have run the calculator at 58 psi rail pressure, 55 psi rail pressure and 52 psi rail pressure and built a IFR table that corresponds to what rail pressure that Manifold Vacuum will generally see.

Perry