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S14SR20DET
12-13-2001, 09:30 PM
Has any one installed a fuel pressure regulator on a S14 SR. If yes, what brand? Does anyone know if the Stillen fuel pressure regulator is a direct bolt on to the SR?

12-13-2001, 10:31 PM
You've already got a fuel pressure regulator. It's mounted at one of the ends of the fuel rail.

If you're talking about a fuel pressure riser, then you don't need it. Fuel pressure risers are a band-aid solution for modified Hondas and other cars that use MAP-based engine management in order to do a VERY rough correction to try and get the A/F ratio closer to correct (MAP systems can't correctly account for the extra air entering the engine if you make modifications, thus the fuel maps are no longer correct).

Asad

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by S14SR20DET:
Has any one installed a fuel pressure regulator on a S14 SR. If yes, what brand? Does anyone know if the Stillen fuel pressure regulator is a direct bolt on to the SR?<HR></BLOCKQUOTE>

S14SR20DET
12-14-2001, 07:17 AM
I know i got a FPR on the car already. I want to go after market because i upgraded the injectors and the turbo. I need to rise the fuel pressure to compensate the injector at high revs.

ADAM HUTCHINSON
12-14-2001, 07:20 AM
i have a cartech rising rate regulator..it gives good control over fuel..and depending on your fuel system can tune it quite accurately

JDMRICE
12-14-2001, 07:29 AM
i am trying to find something that will direct bolt on...no luck yet...
however i found this ...give it a try
http://www.sr20parts.com/parts.html

look down to stillen fuel pressure riser

S14SR20DET
12-14-2001, 09:03 AM
Thanks richard, pete said i need it on my car when koji tune my car. Does anyone know which brand has a gauge right on the regulator so i don't need to get a gauge.

**DONOTDELETE**
12-14-2001, 10:08 AM
You do not need the rising rate regulator. Just the stock 1:1 will work. Actually your stock FPR will work.

You do not need to raise your base fuel pressure with larger injector. But if that's how Pete and Koji suggest, then sure play around.

If you go with the aftermarket units like the SX, you will need to do some modification on the return rail, either have Pete tapped the AN fitting to connect to SX or make an adapter.

Getting something that's stock and bolt on is not any benefit from your stock FPR other than you can rise the fuel pressure that's all.

Wayne http://www.phase2motortrend.com

ADAM HUTCHINSON
12-14-2001, 10:12 AM
if you want to have adjustability for turbo use..and not run like a pig off idle then you 100% need a rising rate regulator!!! these regulators get a bad rap from some...but the cartech unit allows tons of adjustability.....that will come in handy when you are at the dyno....your tuner will need it as he suggested....

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by tristarx:
You do not need the rising rate regulator. Just the stock 1:1 will work. Actually your stock FPR will work.

You do not need to raise your base fuel pressure with larger injector. But if that's how Pete and Koji suggest, then sure play around.

If you go with the aftermarket units like the SX, you will need to do some modification on the return rail, either have Pete tapped the AN fitting to connect to SX or make an adapter.

Getting something that's stock and bolt on is not any benefit from your stock FPR other than you can rise the fuel pressure that's all.

Wayne http://www.phase2motortrend.com<HR></BLOCKQUOTE>

**DONOTDELETE**
12-14-2001, 10:21 AM
Get the XS Fuel Pressure regulator, its pretty nice. But to warn you, for XS to do your fuel setup, its gonna be $$$. But I know they will do it right. Why are you gonna tune your car, I thought it was running fine? Weren't you gonna sell your car?

S14SR20DET
12-14-2001, 10:49 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by KyoshoS13DET:
Get the XS Fuel Pressure regulator, its pretty nice. But to warn you, for XS to do your fuel setup, its gonna be $$$. But I know they will do it right. Why are you gonna tune your car, I thought it was running fine? Weren't you gonna sell your car?<HR></BLOCKQUOTE>
Car funs fine, But i want it to run right!!

formulaJEREMY
12-14-2001, 01:25 PM
While on this topic, does anyone know off-hand what the baseline fuel pressure is for the SR20DET?

SRFiveTen
12-14-2001, 01:31 PM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by King Drift:
While on this topic, does anyone know off-hand what the baseline fuel pressure is for the SR20DET?<HR></BLOCKQUOTE>

i believe it is 43.5psi for all rwd sr20 engines ranging from 140ps to 250ps.

12-14-2001, 03:24 PM
In fact, it's 43.5 psi for all Nissans, and most other cars as well, notably excluding 1G dsm's (36 psi, for some reason).

Asad

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by SRFiveTen:


i believe it is 43.5psi for all rwd sr20 engines ranging from 140ps to 250ps.<HR></BLOCKQUOTE>

SRFiveTen
12-14-2001, 03:29 PM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by asad137:
In fact, it's 43.5 psi for all Nissans, and most other cars as well, notably excluding 1G dsm's (36 psi, for some reason).

Asad

<HR></BLOCKQUOTE>

do 550cc, 555cc or even larger 850cc injectors require higher pressure than the common 43.5psi?

Papa Lazarou
12-14-2001, 03:33 PM
Has anyone here used the HKS or Sard FPR? They are both available with an adaptor to fit the SR. The Sard (Type R) one is a little expensive, was wondering if worth the extra over the HKS?

12-14-2001, 05:30 PM
No. Those flow rates are spec'ed at 43.5 psi. However, if you do change the fuel pressure, the flow rate is given by

F_new = F_old*sqrt(P_new/P_old) (and P_old = 43.5 psi in this case)

Asad

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by SRFiveTen:

do 550cc, 555cc or even larger 850cc injectors require higher pressure than the common 43.5psi?<HR></BLOCKQUOTE>

**DONOTDELETE**
12-14-2001, 06:46 PM
Detuning the fuel at idle is best done at remapping the injector idle map, not lowering the base fuel pressure. Doing so you lower the "entire" fuel map and you will not benefit any from doing this to a high HP single turbo car. Compromising this setup with a rising rate 1:4, or 1:6, will just make tuning more harder and not as linear.

As said, stick with the 1:1 FPR, larger injectors, and a GOOD fuel pump. Come to think of it, I think the fuel pump is the most important. http://www.freshalloy.com/

Tx.

Wayne http://www.phase2motortrend.com

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by ADAM HUTCHINSON:
if you want to have adjustability for turbo use..and not run like a pig off idle then you 100% need a rising rate regulator!!! these regulators get a bad rap from some...but the cartech unit allows tons of adjustability.....that will come in handy when you are at the dyno....your tuner will need it as he suggested....
<HR></BLOCKQUOTE>

**DONOTDELETE**
12-15-2001, 12:31 AM
Rising rate FPR's are typically used as a fuel adder, not simply a "plain" FPR. Many aftermarket turbo kits for non-turbo cars use RRFPR's to add more fuel into the equation.

They DO work, but they are a bit tricky to tune. Also, they are limited on how far you can go - around 85-90 psi of fuel pressure is when injectors start to stick open. Also, running really high fuel pressure levels can be dangerous - more prone to leaks and the like.

With some sort of way of controlling your fuel map (SuperAFC, PowerFC, Haltech, etc.), there's really no need for a RRFPR. Get a good FPR that lets you set your base pressure, and you're fine.

Really, all you need for an aftermarket FPR is one that lets you set the base pressure and has a 1:1 ratio - you get 1 extra pound of fuel pressure for every pound of boost. With an upgraded fuel pump (such as the Walbro) it's common to overpower the stock FPR, leading to higher than desired fuel pressure levels. A good FPR will let you re-set the base pressure, alleviating that problem, as well as being able to keep up with the flow of the better pump.