Jackson FPR Calibration?

[BlownAway]

I'm running with the standard 6 psi setup and have installed the first of 3 gages. The B&M mechanical fuel pressure gage was installed last night and the A/F and electric fuel gage this weekend. (by the way, thanks for those recent postings of gage part nos and pictures)

So the question is, how do I now calibrate the FPR? I've adjusted the "no vac" to 50 psi - the "idle vac" stayed at 48 psi no matter where the adjustment screw was. This seemed to make the car run smoother, but a little rougher at idle.

What are the idle settings with vac and without vac supposed to be? Am I supposed to somehow apply 6 psi to the FPR and check for a higher fuel pressure?

Any help is appreciated.

[Holden]

What is your engine?

Your fuel pressure sounds dangerously low.

Most people here with the stock kit on a GSR run at least 52psi at idle and at least 60psi with no vacuum. I'll bet when you hook up the A/F gauge you'll see that you are running stoich or worse at WOT.

When I had a functioning JR FPR, I was forced to live with high pressures because of my OEM FPR, but I ran at 58psi idle and 72psi with no vacuum.

Now, with a Cartech FPR, I'm at 52psi idle and 65psi without vacuum.

I would lay off WOT until you get the A/F installed or raise the fuel pressure. MAybe the B&M gauge is off. Put the electric one in for a second opinion.

The only way to test WOT fuel pressure is with a FP gauge in the car as you drive (unless you have a dyno). With a JR FPR, you will probably go off the scale (i.e. over 99psi), likely to 110psi or so. That is what it's supposed to do. With the Cartech, I have max psi at 92psi, but you can't do that with the JR FPR.

Greg

[BlownAway]

I called Shawn (Mr. Detail) just to see what they had to say. Here's what he told me:

@ 0 pressure (no vac at FPR with hose capped) I should have 60 psi.
@ idle vac( hose connected) I should have about 8 psi less (= 52, I have 48)
Under boost, I should have a minimum of 75 psi.

He also stated that my 48psi under vac should be OK and agreed that the FPR adjustment screw only adjusts the no press/no vac setting with no affect to the 'with vacuum' reading. I checked my Helms manual and stock pressure (no boost) should be 39 - 46psi with vac. Shawn said the FPR would bump stock pressure up a little.

I'm going to print these posts off to add to the others in my service manual.

Thanks for the help.

[gsrev]

funny how you mention Mr. Detail. I havent seen him post in a very, very, very long time. Wonder if oscar or keith got mad at him for helping us out here on the board since they make it obvious they dont like the idea of us existing. Hmmmm...

------------------
1998 Super Sonic Blue Gs-r
Minor bolt ons include:
Jrsc 6psi.. blah.. blah .. blah..
best 1320: 13.86 @101.82 on street tires