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Jeepman775

300zx injectors Work or no?

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Has anyone been able to get 300zx injectors and variable pressure fuel regulator to work? I am gonna try, but I fugure I should ask if anyone has made this work GOOD yet I read the old posts about it and think there is potential there. Also anyone got any tricky hints about it?

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i think you should upgrade the stock fuel pump before you try and max it out. its only rated to about 45lbs of pressure.

 

if they fit, you should be able to tune it in... i still havent heard about a rising rate fuel pressure regulator being thoroughly tested. with the stock injectors.

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the stock pump will make well in access of 45 PSI. we have a race car that runs something like 50 PSI at idle, and more on boost. that is with the stock pump
It isn't a bad Idea for me tho. It's got some miles tends to make some ugly sounds, People think I have a bunch of yaks under my car when I start is up

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I just checked out some prices It's not to to bad I can manage it. I will start this once I get my boost controller, intercooler, boost gauge and BOV working, ohhhh yea and engine swap done. wiring harnesses suck

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aight, i was gettin my info from a napa book i was looking at when picking the pump im runing now. ford f150 external. 90psi 50 gph

 

y 50 psi at idle?

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Ignorance Alert!: Every time people talk about RRFPRs I get a little confused. It seems to me that either a) my manual is wrong, B) I misunderstand what the manual says, or c) RRFPRs are a "band-aid" that would better be solved by other means.

 

So, would someone please tell me how they are different from an EA82T's pressure regulator, or why they are needed.

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ok...basically...the stock Fuel Pressure Regulator is in effect a "rising rate"

 

When you pressurize the intake track, you need to increase the fuel pressure so you have the same "pressure differential" between the fuel line side and the intake track.

 

The stock fuel pressure regulator increases fuel pressure 1 PSI for every 1PSI of boost, so it's a 1:1 RRFPR (rising rate fuel pressure regulator)

 

Rising rates are available, and most times adjustable for different ratios. Usually like 5:1, 7:1, 9:1, and 12:1 is probably as high as you'll find.

 

With the stock fuel pressure regulator at 10 PSI of boost you will have stock pressure + 10 PSI

 

With a RRFPR even with a 5:1 ration, at 10 PSI you'll have stock pressure + 50 PSI. So close to 100 PSI of fuel.

 

RRFPR's are a crude, and cheap way to add more fuel. They are cheap compared to electronics, but don't have anywhere close to the tunability. They are somewhat of a Bandaid fix. On our race car, the RRFPR will be coming out in favor or fancy electronics. it's just what we had available at the time.

 

I really wouldn't screw with a RRFPR...your gonna end up spending something like 100-200 bucks on one, which is half way to decent piggyback comptuers.

 

not to mention...some of those fuel lines under the car which are getting close to 20 years old aren't going to like the 100 PSI.

 

 

And 50 PSI at idle. we needed to raise the baseline pressure to keep the motors rich and cool enough, so we don't end up with melted/broken pistons

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Thanks, DIS. Pretty much what I thought, but couldn't believe that people would go through the trouble and expense to put in what I could only think of as a kludge. Better fuel management sounds much better and cheaper than arbitrarily dumping extra fuel and an escalating rate.

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but realy that is all you need. one more lb of fuel to every lb of boost your running. dial in the disty, and your good.

when peepl buy a turbo kit for a honda, it comes with a check ball for their map sensor, and a rrfpr. works very well, not a bandaid.

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I think I'll just get the MegaSquirt setup. Would probably work better AND you'd have more tuning capabilities when it comes to your fuel pressure I believe.

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