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Rising Rate Fuel Pressure Regulator


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10 replies to this topic

#1 Myxalplyx

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Posted 07 February 2005 - 02:33 AM

Can someone tell me if this would work on an EA82T?

http://cgi.ebay.com/...sspagename=WDVW

Posted Image


If I can use this, is this to be put in upstream (before), downstream (after) or in place of the stock fuel pressure regulator.

#2 nkx

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Posted 07 February 2005 - 02:39 AM

RRFPRs are kind of a bandaid. its used instead of upgrading your fuel pump and injectors, however i can kinda see the usefulness of it on our cars due to the lack of high flow injectors.

#3 RavenTBK

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Posted 07 February 2005 - 10:38 AM

If I can use this, is this to be put in upstream (before), downstream (after) or in place of the stock fuel pressure regulator.

The answer is "C", in place of. Adjust the base rate to match the stock regulator, and run. We use rising rate regulators on our turbo Datsun ZXs.. common swap with okay results.

As for if you can use it on your EA82T, that is unknown to me. I'm a pushrod guy. :D

#4 grossgary

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Posted 07 February 2005 - 11:07 AM

kevin,
john (from ky) suggested using these as a simple solution to turbo issues so i'd post over there and see if you can get his input. put "turbo" in the thread title and i bet he responds. he is the man.

#5 All_talk

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Posted 07 February 2005 - 11:42 AM

From the Ebay add...

"Vacuum/Boost Reference on a 1:1 ratio."

This is the same ratio as the stock regulator, this one will let you adjust the base pressure, but I dont see how this type of regulator will allow you to add fuel to the top end without adding it at cruse and idle as well. What you need is one that lets you adjust the rate as well as the base pressure (read that BIG $$).

Gary

#6 4WDFrenzy

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Posted 07 February 2005 - 01:46 PM

I have an RRFPR on my GL-10 that is made by Stillen. I adjusted my base fuel pressure to 38psi and my car runs just fine. It idles with no problem and runs great in the upper rpms. I'm not sure what the rate is on it, but it seems to add plenty of fuel on up top and I have noticed no increase in fuel usage while cruising, only when in boost. But that is right where it should be.

#7 Myxalplyx

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Posted 07 February 2005 - 01:54 PM

From the Ebay add...

"Vacuum/Boost Reference on a 1:1 ratio."

This is the same ratio as the stock regulator, this one will let you adjust the base pressure, but I dont see how this type of regulator will allow you to add fuel to the top end without adding it at cruse and idle as well. What you need is one that lets you adjust the rate as well as the base pressure (read that BIG $$).

Gary


Gary, this is what I was getting at. I wanted to get one that doesn't adjust the base pressure BUT you can adjust the ratio of increase you where you want it to (1:1, 2:1, 3:1). I don't want to adjust the stock fuel pressure as around town driving is just fine. I just want to adjust the rate of increase of fuel pressure based on how much boost I'm running. So, when I test it out, if 2:1 isn't enough, I can adjust to 3:1......test......not enough.......4:1.

The one I posted about above doesn't seem clear as to if it's just a 1:1 fpr or adjustable. The words interchange throughout the ad. I emailed/PMd the seller.

#8 garner

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Posted 07 February 2005 - 02:21 PM

Myx,

That RRFPR would work dandy. I have an MSD (made by Bosch about $60) that is 1:1 ratio but adjustable base. Worked well on stock ecu, but doesn't have the "bling" appeal of ther ebay one. Looking at your AFRs from your last dyno runs, they don't look too bad. I'd try turning up the boost until you see a dramatic dive. Wide band O2 would be really handy....


Keep in mind, like people say, RRFPRs are bandaids. You can crank up the pressure and get slightly more fuel per squirt but don't over do it. I found when I cranked mine up, I'd actually run way to rich under boost. I think at some point the injectors will start to leak under high pressure. (just a guess). The RRFPR kind of complicates Megasquirt tuning but does assure richness under boost.

If you aren't ready to go Megasquirt. Your money might be better spent on some larger injectors

#9 4WDFrenzy

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Posted 07 February 2005 - 06:21 PM

Hey Kevin, I don't mean to threadjack you or anything, but I just wanted to update my FPR psi from what I posted earlier. I upped the fuel pressure to 42psi and my car pulled the hardest that it ever has before today. And the good part is, it is still idling just fine. Just thought I would update everyone, or at least everyone who is interested. I'm sorry for the interruption.

Patrick

#10 Myxalplyx

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Posted 07 February 2005 - 06:34 PM

Hey Kevin, I don't mean to threadjack you or anything, but I just wanted to update my FPR psi from what I posted earlier. I upped the fuel pressure to 42psi and my car pulled the hardest that it ever has before today. And the good part is, it is still idling just fine. Just thought I would update everyone, or at least everyone who is interested. I'm sorry for the interruption.

Patrick


Patrick,

No biggie! Your thoughts aren't thread jacking. It's just the kind of info that's useful actually. You jacked it up to 42psi base fuel psi from what? I don't know what the base fuel psi is (I should've looked in the FSM when I was home).

If that fuel pressure regulator on Ebay is just fine and it's adjustable from 1:1 to higher like 2:1 or 3:1, then I'll take a swing at it. I appreciate all the help.

#11 calebz

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Posted 07 February 2005 - 06:49 PM

Stock FPR regulates at ~36psi above manifold pressure.

38-42 IMO is still well within the tolerances of the rest of the fuel system

Any more, and I think it would start to overpower the injectors, and overdraw the pump.




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