Fuel Pressure regulator

[chris52]

I am thinking of putting a fuel pressure regulator on the griff 500 serp to try keep the rail pressure constant.
So my question is what pressure should I set it at?

Chris

[steve-V8s]

Um. I rather suspect you already have one.

[chris52]

Ok I shall rephrase I am thinking of putting an adjustable fuel pressure regulator on my griff

Chris

[chris52]

Has anyone fitted an adjustable fuel pressure regulator to there car??
Any help would be much appreciated

Chris

[steve-V8s]

Just out of interest why do you want to do that? You must have some reason in mind. Is it running rich or lean with the current system ?

[Mr MoJo]

Hi Chris, I had Ian of Torque V8 fit one of his to my car at The Growl. Made a big improvement on the Rollers the next day (was running quite lean prior).
For the life of me I can't recall the pressure though (it's either 2 or more likely 3 bar I think).

eta I'll check next time the car is out.

Edited by Mr MoJo on Thursday 22 October 17:11

[chris52]

Cheers Simon

steve-V8s said:

Just out of interest why do you want to do that? You must have some reason in mind. Is it running rich or lean with the current system ?

When it was on the RR at the growl I was told it was running realy lean, Simon (Mr Mojo) had the same issue as me at the growl and had one fitted which improved its running significantley especially after fitting the smoothbore pipes from act.I have also had the smoothbore fitted and the car has lost a little performance since so was thinking I would give it a try, just didn't know what pressure to set it at.

Chris

[GreenV8S]

2.5 bar is the usual pressure - without vacuum. But if it's been mapped with a different pressure, that's what it needs to be supplied with.

[chris52]

GreenV8S said:

2.5 bar is the usual pressure - without vacuum. But if it's been mapped with a different pressure, that's what it needs to be supplied with.

Cheers for the info thats great

Chris

[Mr MoJo]

Yep, checked tonight, 2.5 bar.

Love the little pressure guage too !! The difference of 9 bhp up from standard and 17 bhp up on having just the ACT kit fitted was well worth the money. I feel the full TorqueV8 AFM kit coming quite soon Some of the results at this years Growl (Tavan's car for instance) were quite impressive with just this kit fitted.


Here it is fitted.

Edited by Mr MoJo on Friday 23 October 19:58

[blitzracing]

I bought one of those Ebay jobbies, worked well enough for a couple of years, but ended up leaking fuel pressure down due to the way the diaphram shuts the fuel off as its very vunerable to specks of dirt in the fuel getting embedded in the soft valve material. It was also a b*gger to keep the pressure spot on, as the ajustment thread is pretty course, and a fraction of a turn makes a big difference. Overall, tweeking the fuel pressure should only be done whilst either monitoring the lambda voltages at full load (good probes will give about 1.2 volts at peak fuelling), or on the rollers. The down side is if you get it spot on at full power (lets say your car was running lean flat out) it may then over fuel at mid range (above 3400 rpm). If you have catalysts the ECU will try and take care of mixture below 3400 rpm, but it can lead to shunting if you hit the ECU's correction limits. Also unfortately if you go rich enough to stop the ECU controlling the mixture closely it will stop the catalysts working, and could overheat them. The 14CUX is how ever very tollerant to abuse, so you can try up to about 40psi, but Id would not go higher.

Mark