Fuel pressure regulator

Gary57 · Post by **Gary57** » Thu Nov 02, 2006 12:18 pm

I wanting to get a fuel pressure regulator. BUT i want the presure on idle to be the same as it is now and at full boost it must be 4Bar instead of 3Bar. I think this called a progressive regulator and will work off the manifold pressure and vacuum.

WooHaa · Post by **WooHaa** » Thu Nov 02, 2006 4:38 pm

A standard one will work fine.
I have one, & it looks exactley like the standard one, but BIGGER!!!

Gary57 · Post by **Gary57** » Fri Nov 03, 2006 12:08 pm

So you can adjust the std one to give more pressure on boost but on idle it will remain 1.8Bar??

Phinx · Post by **Phinx** » Fri Nov 03, 2006 2:06 pm

Your best bet is to buy a Nismo FPR they can be adjusted and are progressive they are around R 1100 .

They fit to the stock fuel rail and will allow some good tunning with later mods.

Gary57 · Post by **Gary57** » Fri Nov 03, 2006 2:09 pm

Where from?? Do you get aftermarket ones??

Vlade · Post by **Vlade** » Fri Nov 03, 2006 2:52 pm

There is plentura AM units available... They all basically fit/work

Gary57 · Post by **Gary57** » Mon Nov 06, 2006 8:22 am

Yes but are they all progressive?? I dont want the pressure to go on idle.

Gary57 · Post by **Gary57** » Mon Nov 13, 2006 2:11 pm

Does no one have a progressive fuel pressure regulator?? I have checked most but none are progressive. Does rezlo have??

Gary57 · Post by **Gary57** » Tue Nov 28, 2006 4:02 pm

Can the STD FPR be adjusted?? Where can you get progressive/rising rate ones from??

Sokar · Post by **Sokar** » Wed Nov 29, 2006 7:44 am

Yep, Rezlo has FPR's, Rezlo has everything

Any FPR with a "vacuum/boost" nipple on it should be progressive as it uses the manifold pressure to regulate, the nizmo one Phinx mentioned and others are manually adjustable to fine tune what you want.

Hennie Marais · Post by **Hennie Marais** » Wed Nov 29, 2006 1:40 pm

I'm using a Nismo one, very nice and adjustable, fits perfectly on the rail, just a crappy job to fit if you strip the screws because then you have to remove the intake manifold and I hate it, al those brackets and 1000 waterpipes.

ChemCool · Post by **ChemCool** » Sat Jan 27, 2007 3:58 pm

Just help me out here please. Progressive= rising type FPR and opposite called static? Then I am confused. One source from the net, Aussie I think, advice to use static rather non rising and set to 36PSI? What now??
Also need to go this route with new feul pump needed soon?

veecee · Post by **veecee** » Sat Jan 27, 2007 8:19 pm

i am using a rising rate FPR, and i have had no problems at all with my fuel.

the standard nissan FPR works in the same way, it controls fuel pressure based on the level of vacuum, or boost, in the plenum chamber.

its even controlled with a solenoid via the engine computer.

mine goes up in a 1:1 ratio as far as i know, but i have seen another option available with a higher ratio - 1:1.7

i say check out there, you dont have to spend 1100 on the nismo item. i think i paid about 400 for mine! and it came free with an adapter that fitted straight onto my fuel rail.

easy mod.

ChemCool · Post by **ChemCool** » Sat Jan 27, 2007 10:19 pm

Veecee, need to take this one up with you. Will chat soon or phone . Thanks. But I am editing this thread and copy all this info from an Aussie on FPR.And I quote him" How to set your fuel pressure via an aftermarket FPR / fuel pressure regulator 7:19 AM 12/11/2006

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Ok, so I've seen this question pop up a lot, and as much as I love to repeat myself, I've decided to make an official thread and then link to it in the stickies so that....well I don't have to keep repeating myself!
First off, I'm going to give some general info on fuel pressure regulators. Then I'll give a step-by-step on how to set the fuel pressure. If this sounds weird it's because I'm copying and pasting from an email I just wrote.

Althought just about any FPR can be made to work the SR NISMO one is the easiest. The PN is; 22670-RR580 and looks like this;

You will have to use a longer peice of hose as the angle on the outlet is wrong and you will have to loop it around to make it work. Many of us have been running them like this for years with out a problem.

In answer to your questions, no, the stock FPR isn't a rising rate, and you don't want a rising rate. They use rising rate FPR's on NA cars that have been converted to forced induction (turbo/supercharger). Since our ECU already has all of the info it needs to add the correct amount of fuel based on the input it's receiving from it's various sensors, all you need to do is give the fuel injectors 36psi static pressure and everything should be OK. If you use a rising rate FPR, your AFR's will get horribly rich as boost pressure increases. As for the 90° hardline, yea, you can remove it.

Static fuel pressure is the fuel pressure that is in the rail relative to the vac/pressure in the manifold. The purpose of a fuel pressure regulator is to give the injectors a relatively constant amount of fuel pressure so that the ECU is easier to program. Here is what I mean; under vacuum, with out a fuel pressure regulator, MORE fuel would be injected than normal since the manifold is "sucking" the fuel into the rail. To compensate for this, the FPR drops the pressure in the rail so that not as much fuel is available to be injectors. The opposite happens under boost. The pressure in the manifold pushes back on the fuel trying to come out of the injectors. With out a fuel pressure regulator, you would have to keep the injectors open longer, or use bigger injectors, which can make having a smooth idle difficult. With the FPR installed, when the boost pressure in the manifold increases the regulator increases the pressure in the fuel rail in a linear proportion so that the same relative amount of fuel is injected. AKA, with vac fuel pressure goes down, with boost, fuel pressure goes up.

It is nearly impossible to set static fuel pressure with the motor running, so don't bother trying. Here is how I do it;

ChemCool · Post by **ChemCool** » Sat Jan 27, 2007 10:28 pm

Then he goes on how to fit. But hope this link to work for all to read then.
Do I then understand this wrong? Can you see now why i am still confused. Running richer is not good - agree?
http://forums.nicoclub.com/zerothread/214558