FPR for BOOST

[jules325i]

can i use the standard 3 Bar Fuel pressure regulator or do I need a rising rate regulator.

Ill be running 2.8 m20 15PSI 80lb Injectors and E85.

[Northern]

Standard FPR if you have a standalone or another method of fuel control. I assume you do with that setup haha

[nando]

no you don't want a rising rate regulator, you want an aftermarket computer that can handle boost and E85.

[dirtie30]

I would suggest a pnp MS setup along with a 1:1 FRP. Static fuel pressure isn't ideal for boosted setups, but of course that all depends on the tuning.

[nando]

a standard FPR is 1:1. ;)

[dirtie30]

huh. The stock FPR looks like a standard rising rate fuel pressure regulator to me, not a true 1:1. Interesting.

[nando]

no. it's 1:1. all standard FPRs are 1:1. this keeps the fuel pressure at the injector constant relative to manifold pressure. it's necessary to keep the fuel output linear which is what the computer will always expect.

a RRFPR would have a ratio like 1:5, 1:8, etc. this makes fuel injector response non-linear, which is a bad idea. RRFPRs haven't been a good idea for a decade at least. They were a decent band aid solution before you could build a standalone for $200 but they're pointless now.

[dirtie30]

No shit, that's why I suggested a 1:1 because the stock unit looks almost identical to all the old VW RRFPRs I've messed with, so I just assumed it was rising rate.

[jules325i]

Ok yes I have a link g4plus xtreme ecu.
Thanks for the input.

[jules325i]

I'll post some pictures and dyno results when the car is finished, by the end of the year.