Fuel Pressure Regulator for 3.0 (2005)

[nixwrx]

Hi guys –Saw this thread, and could use some help/advice…

viewtopic.php?f=17&t=31812

Fuel pressure at idle (under vacuum) is sitting at 50psi, so the fuel pressure regulator looks to be on its way out or is already pretty much dead. FYI the current tune is compensating for this and I’m taking it easy with the car (and will get a re-tune at the same time as the mechanical fix).

Car is a 2005 3.0RB. The FPR itself and damper look to be an integrated assembly? I think it’s 16622AA010 from Subaru and an OEM replacement looks like silly money – around $500 AUD.

Since I’m running the Kobe 265 fuel pump and 565cc STi injectors and planning to go supercharged + E85, I think it’s time to go aftermarket for something a bit more robust. I’m looking at the Turbosmart FPR800. Just a few questions:

1) Will the FPR800 drop in ok – anything about this unit that wouldn’t work with the 3.0?

2) As I understand it, the OEM setup has the damper separate to the FPR itself. If I remove that entire assembly and drop the FPR800 in, will some sort of damper also be required in addition to the FPR800?

3) Out of the box the FPR800 works with 1/8 connectors. Any idea what the stock diameter is?

4) What should base fuel pressure be for the 3.0? I’ve seen around 38psi and around 43psi quoted, and I’m not sure if there’s variance between the 3.0 and turbo models.

I’ll figure out as much as I can on the above but also wanted to see whether anyone has direct experience with this unit or the FPR1200, etc.

Thank you!

Nik

[BillyCorgi]

From Gne4 Pre Facelift H6 FSM

image sharing sites

[nixwrx]

Legend thanks BC

I'm thinking that if I run the new FPR at 3bar/43psi then it should - all other things going well - have the injectors flowing at their "advsertised" rate

I'm assuming that 3bar is the underlying assumption in most instances when flow rates are published

[KiDo_Tuning]

Legend thanks BC

I'm thinking that if I run the new FPR at 3bar/43psi then it should - all other things going well - have the injectors flowing at their "advsertised" rate

I'm assuming that 3bar is the underlying assumption in most instances when flow rates are published

Correct. As per OEM specs for fuel pressure

[nixwrx]

Er sorry guys I've probably confused myself here:

The instructions from the FSM seem to read (to me) that when the vac hose is disconnected, that fuel pressure should be around 50psi. And then when RECONNECTING it, fuel pressure should then be around 43psi.

However I've seen the exact opposite advice elsewhere - that the FPR should be set to 43psi with the vac hose DISCONNECTED, when then would presumably provide a reading in the high 30's when reconnecting the vac hose.

So - under what conditions should fuel pressure be set to 3bar/43psi? With the van hose connected or disconnected?