CJM Mini FP Gauge Kit

phunk

that is an example of a unhealthy fuel pressure curve. a side effect of upsetting the balance in the fuel pump module by putting a larger pump in without making the proper modifications to accommodate the much higher bypass fuel volume.

your fuel pump is overwhelming the regulator and/or venturi passages behind it. i am guessing you have larger than a 255lph in there to see as high as 72. the canister fill venturi on the bottom of the fuel pump module can be opened up a bit to bring your pressure back down. (this can serve as a reminder to me to work more on my (not-yet-so) "ultimate fuel pump" thread.

the pressure comes down when you start burning more of the fuel because there is less volume that the regulator has to relieve, and backed up pressure from the venturi blockages begins to lower

so the issues are correctable. if your A/Fs are staying inline, there is no immediate rush to resolve it.

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jwick

I'm running the 340lph. AFRs are pretty good. Closed loop I stay between 14.7-15.2. Open loop I'm mid 11's under load. It goes a little rich if I apply throttle a real low rpms (like being in 2nd under 1500 rpms and accelerate in traffic). It clears up almost immediately.

Since AFRs are pretty good I figured I would wait until the S1 upgrade. Will that fuel return setup completely fix my issues? Or will we need to discuss other fixes?

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'10 G37T 6MT Graphite/Graphite - BP - G37T Build

phunk

Ah yes when I did the 340 pump originally I also saw the very large idle spikes. Drilling out of the canister fill venturi to just over 100 thousandths brought it down somewhere into the 50s which was good enough for me.

S1 system will help promote a healthy curve as you go up in power/boost... but the current idle pressure spike you have is a side effect of the pump and the fix for that is unrelated to the RFS upgrade. The RFS will still run the venturi's so the venturi flow has to be opened up a little to fix that idle spike.

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jwick

I'll admit I'm not absolutely sure what you are referring to being drilled. Do you offer an upgraded tube that wouldn't require drilling? The thought of doing something not reversible leaves me a little uneasy.

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'10 G37T 6MT Graphite/Graphite - BP - G37T Build

phunk

It is a little plastic venturi that attaches to the bottom of the fuel pump module. Unfortunately this little guy is not available purchased separately... so there is no going back if you went back to stock.

To put a stock fuel pump back in there with the oversized venturi would weaken the over-tank siphon and promote fuel starvation.

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COSMO

I drilled mine out to 101-thousandths. Have a pic if you want to see?

phunk

COSMO has a picture as I recently had him do it for his pump. I will also try and get this added to my fuel pump thread quickly.

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jwick

Sure. Send it my way

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'10 G37T 6MT Graphite/Graphite - BP - G37T Build

COSMO

Must have deleted it off of my phone but Charles has a pretty good pick of it.. Sorry

phunk

Work in progress right now: CJM: Ultimate 370z Fuel Pump Thread

Should have it done in the next 30 min.

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jwick

Think that's the wrong link. You just linked to some baby dying in street race

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'10 G37T 6MT Graphite/Graphite - BP - G37T Build

phunk

LOL i dont know man, the link works for me. I havent seen anything about the street racing baby though.

Here is the entire thread I am working on it in. CJM: Ultimate 370z Fuel Pump Thread

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jwick

Maybe my phone is crackheaded

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'10 G37T 6MT Graphite/Graphite - BP - G37T Build

jwick

Now that I quoted it, the quoted link works fine. I'm done with android, guess apple gets my money at upgrade time

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'10 G37T 6MT Graphite/Graphite - BP - G37T Build

phunk

Got that section done for ya!

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