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Maximum fuel pressure

Sourskittle

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#1
What is the maximum our fuel pressure system should be run at on the HPFP side? Stock is around 2111psi or something like that. Could run it at 2600psi if we needed it to? How about 3000psi?
I think the new sky-activ mazda's run 2800psi, but of course..... This ant no mazda.

Opinions ? Guesses? Braden? Ian ? Razor ? Boogie man ?
 


DHM1

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#3
What is the maximum our fuel pressure system should be run at on the HPFP side? Stock is around 2111psi or something like that. Could run it at 2600psi if we needed it to? How about 3000psi?
I think the new sky-activ mazda's run 2800psi, but of course..... This ant no mazda.

Opinions ? Guesses? Braden? Ian ? Razor ? Boogie man ?
I do some prototype DI stuff for a few of the manufactures and we are using all the same lines and pumps up to 200bar (2940psi) I dont see a problem getting closer to the 2800 mark but i think the feed/pick up pump is more of a issue at that point.
 


OP
Sourskittle

Sourskittle

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Thread Starter #4
My lpfp is MAXXED. 100% duty cycle. 12.4 volts, and 92psi
 


razorlab

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#5
Looks like your HPFP is still keeping up. Log your injector IPW too. I actually haven't logged my LPFP yet with the E40.

Thanks for the reminder. I'll try to get a log tomorrow so we can compare
 


RAAMaudio

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#6
I have a 255 Walbro pump, I wonder if it would fit out cars? I can make adapters if needed unless I could find the parts.

Just checked, glad there is an access port under the rear seat, I could pull it and take a look but I would want to know at least if the 255 is enough pump, seems it should be as was on my Forester XT that got 7.8 or so MPG at track events on 100 Octane.

Then again I do not know what the LP pump requirements are for this car, any idea?

I need to supply enough fuel for the modded turbo and E30 and maybe later an EFR on E30.
 


razorlab

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#7
There is no way the lpfp is maxed, I would look elsewhere.

ATP's testing was with a turbo that flowed a billion lb/min more and didn't have issues until 300+ whp.

I will bet my life savings either of you aren't even close to that, it's simple math really.

That said, DW has a in tank lpfp upgrade that flows 256lph I believe.
 


OP
Sourskittle

Sourskittle

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Thread Starter #8
Walbro 255 is more pump than this car would likely ever use. The hpfp is gonna be the limiter. The svt focus pumps were used a lot for some reason, weren't they 190lph ?
 


RAAMaudio

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#9
Duh, I forgot about the ATP GT28 and GTX, of course they would require far more fuel so unless they changed the stock LPFP then it will be fine, great, less to do!

I guess I will sell the Walbro pump then.
 


DHM1

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#10
There is no way the lpfp is maxed, I would look elsewhere.

ATP's testing was with a turbo that flowed a billion lb/min more and didn't have issues until 300+ whp.

I will bet my life savings either of you aren't even close to that, it's simple math really.

That said, DW has a in tank lpfp upgrade that flows 256lph I believe.
I agree if atp really found the end of our fuel then we will be good to go for the same 310 hp on gas. But I still think the HP system has room to go if the LP system was upgraded. If not we should hunt down someone to upgrade our HP fuel pump.
 


razorlab

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#11
My lpfp is MAXXED. 100% duty cycle. 12.4 volts, and 92psi
So I did some looking around at some stats on my commute this morning. I'll do some actual logs later but for now, here are some data points from my car.

Lowside FP Actual (psi)
70-75 approx @ idle
85-93 approx @ WOT
101-104 approx @ overrun

Lowside FP DC (duty cycle %)
104-107 approx @ idle
145-170 approx @ WOT

So pretty much inline with you, but with a little higher duty cycle, which makes sense since I'm running E40.
 


OP
Sourskittle

Sourskittle

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Thread Starter #12
My laptop ( that i hated) die this morning. Like... DEAD and not coming back.
 




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