What fuel pressure? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

trqless · 03-02-2006, 03:01 PM

I just bought a nismo fpr and a gauge that will go on the fuel return line, what psi do i set the fpr to? And is that with the vacuum hose attatched or not? Because on my honda i was told to have the fpr not connected to the vacuum source when setting the pressure.
Thanks

neverlift · 03-02-2006, 03:20 PM

ing like 35 with and 43 w/o vac don't quote me .
don't have manual in front of me,this is for ka24e

trqless · 03-02-2006, 03:30 PM

Quote:

Originally Posted by neverlift

ing like 35 with and 43 w/o vac don't quote me .
don't have manual in front of me,this is for ka24e

Does anyone know what it is for an sr20det? or is it the same?

stevesr20 · 03-02-2006, 08:18 PM

I THINK its 43 stock vac line on... search for it though, i did, it's out there bro.

Suk02Si · 03-02-2006, 08:35 PM

its 2.5 Bar which equates to roughly 36 psi

SoSideways · 03-02-2006, 10:34 PM

Yup, with vacuum line off it should be 43psi, with vacuum line on it should be 36psi.

This is at idle by the way.

kuramaya · 03-02-2006, 11:29 PM

3 Bar with vacuum line removed and thumb over the hole..

*fliprayzin240sx* · 03-03-2006, 01:36 AM

between 36-42 psi with no vaccum line for stock boost. But if your bumping your boost to 14 psi, crank the fpr close to 60 psi before it starts hesitating.

stevesr20 · 03-03-2006, 05:16 AM

wow! my fp has to be at 55psi to give me a decent a/f ratio on my aem wideband (WIDEBAND NOT NARROW BAND) thats with the vac line ON... my a/f is 12.7 13.0 at 14psi. 12.5 a/f at 10psi.... wierd, can't figure out why either, (I know thats not normal) tried swapping out injectors, fuel rail, ecu, wireing harrness, and 02 sensor... all had no effect. so i bought a fpr and turned up the fuel pressure. at 43psi vac line on, my a/f was in the high 13's witch to me is lean as hell... so i turned up the fuel pressure to 53psi vac line on.... I know it's not good for the injectors, luckly i only drive it on sundays, and will be upgrading my hole fuel package soon... I am under the impression the motor and turbo are stock, but I can't figure out where all this extra air is coming from... the motor had a adjustable wga on it and a piggy back of some sort when i got it.... So the guy was a tunner. only thing i can think of is maybe a clipped turbo i dunno..... car feels strong for what it is. guess a dyno is the only way to find out.

PhopsonNY · 06-29-2006, 01:38 PM

Quote:

Originally Posted by stevesr20

wow! my fp has to be at 55psi to give me a decent a/f ratio on my aem wideband (WIDEBAND NOT NARROW BAND) thats with the vac line ON... my a/f is 12.7 13.0 at 14psi. 12.5 a/f at 10psi.... wierd, can't figure out why either, (I know thats not normal) tried swapping out injectors, fuel rail, ecu, wireing harrness, and 02 sensor... all had no effect. so i bought a fpr and turned up the fuel pressure. at 43psi vac line on, my a/f was in the high 13's witch to me is lean as hell... so i turned up the fuel pressure to 53psi vac line on.... I know it's not good for the injectors, luckly i only drive it on sundays, and will be upgrading my hole fuel package soon... I am under the impression the motor and turbo are stock, but I can't figure out where all this extra air is coming from... the motor had a adjustable wga on it and a piggy back of some sort when i got it.... So the guy was a tunner. only thing i can think of is maybe a clipped turbo i dunno..... car feels strong for what it is. guess a dyno is the only way to find out.

Hey Steve... did you ever find out what was causing this?

far1002 · 03-03-2006, 06:34 AM

its your fuel pump its not pumping enough fuel.

stevesr20 · 03-03-2006, 11:57 AM

Quote:

Originally Posted by far1002

its your fuel pump its not pumping enough fuel.

It's the upgraded walbro...

kuramaya · 03-03-2006, 02:04 PM

Thats weird cause I run a wideband on my car all day and night and I am at 11:1 at .9 Bar of boost with stock 370's and 3 Bar fuel pressure set with Nismo FPR and Walbro 255...something is not right...

trqless · 03-03-2006, 02:24 PM

Right now my peak is 12 psi. Just got in the fpr today, about to go and put it on, hopefully it will solve my starting issues as the rail is not holding fuel, it just dumps it back into the tank after the car has been sitting.

stevesr20 · 03-03-2006, 06:16 PM

Quote:

Originally Posted by bjorkluv

Thats weird cause I run a wideband on my car all day and night and I am at 11:1 at .9 Bar of boost with stock 370's and 3 Bar fuel pressure set with Nismo FPR and Walbro 255...something is not right...

thats, a nice a/f right there, thats what im use to seeing. i have to max my injectors out to get a 12.5 which i don't like running with out race fuel. i two have a wideband in the car all day and night, i run the aem wideband and im really happy with it... i will never own a forced induction car with out one... to me its stupid. 280 bucks and it has saved my car.... my car was stupid lean high 13.'s and i never would have known. car ran fine. a little slower than now but i did'nt know any better being it was my first sr. got the bund welded in and the wideband showed me stupid lean... i don't know what the car has done but i have talked to enjuku and scott about it. and i must be getting extra air from somewhere either a cliped turbo or head work cams something... a dyno will tell if any of that is fact but for now i am needing the extra fuel and have trouble shooted the entire system turning the fuel pressure up was the only solution... I even exchanged the wideband thinking it was bad....

kuramaya · 03-04-2006, 01:16 AM

Quote:

Originally Posted by stevesr20

thats, a nice a/f right there, thats what im use to seeing. i have to max my injectors out to get a 12.5 which i don't like running with out race fuel. i two have a wideband in the car all day and night, i run the aem wideband and im really happy with it... i will never own a forced induction car with out one... to me its stupid. 280 bucks and it has saved my car.... my car was stupid lean high 13.'s and i never would have known. car ran fine. a little slower than now but i did'nt know any better being it was my first sr. got the bund welded in and the wideband showed me stupid lean... i don't know what the car has done but i have talked to enjuku and scott about it. and i must be getting extra air from somewhere either a cliped turbo or head work cams something... a dyno will tell if any of that is fact but for now i am needing the extra fuel and have trouble shooted the entire system turning the fuel pressure up was the only solution... I even exchanged the wideband thinking it was bad....

good reply...I have the same wideband on mine...I have to put the 550's in soon..I am sure I am maxing out my injectors...I have only been running such high boost for about a month after putting in the wideband and the TVVC. I only get the 11:1 at full throttle and boost though..normal driving and it is all over the place but still 13 or lower..the SAFC II is a bitch stupid bitch to tune for low throttle..

03-02-2006, 03:01 PM	#1
trqless Leaky Injector Join Date: Feb 2006 Location: Winchester, VA Posts: 63 Trader Rating: (0) Feedback Score: 0 reviews	What fuel pressure? I just bought a nismo fpr and a gauge that will go on the fuel return line, what psi do i set the fpr to? And is that with the vacuum hose attatched or not? Because on my honda i was told to have the fpr not connected to the vacuum source when setting the pressure. Thanks

03-02-2006, 03:20 PM	#2
neverlift Zilvia Member Join Date: Jan 2006 Location: DUVAL Posts: 166 Trader Rating: (0) Feedback Score: 0 reviews	ing like 35 with and 43 w/o vac don't quote me . don't have manual in front of me,this is for ka24e __________________ derp derp

03-02-2006, 08:18 PM	#4
stevesr20 Join Date: Dec 2005 Location: fl Posts: 42 Trader Rating: (0) Feedback Score: 0 reviews	I THINK its 43 stock vac line on... search for it though, i did, it's out there bro. __________________ ------03' 400whp solar yellow srt-4 (R.I.P.) ------05' white srt-4 [email protected] (she is missed) ------04' HEMI quad cab 4x4 (daily driver) ------91' hatch (swapped sr20 det) ------Afghanistan (04'-05')

03-02-2006, 11:29 PM	#7
kuramaya Nissanaholic! Join Date: Dec 2004 Location: 沖縄 , Japan Age: 52 Posts: 1,677 Trader Rating: (1) Rides Gallery: kuramaya Feedback Score: 1 reviews	3 Bar with vacuum line removed and thumb over the hole.. __________________ ZEROYON WEBSITE IS HOMO NEW SITE: blacklinux.com/innersanctum/index.php

03-03-2006, 01:36 AM	#8
fliprayzin240sx Man w/ CTSV & a Car Seat Join Date: Aug 2002 Location: Tampa Posts: 17,998 Trader Rating: (19) Rides Gallery: fliprayzin240sx Feedback Score: 19 reviews	between 36-42 psi with no vaccum line for stock boost. But if your bumping your boost to 14 psi, crank the fpr close to 60 psi before it starts hesitating. __________________ If you think Zilvia has too many assholes... CLICK HERE!!!

03-02-2006, 08:35 PM	#5
Suk02Si Zilvia Addict Join Date: Dec 2004 Location: Los Angeles Age: 42 Posts: 831 Trader Rating: (8) Feedback Score: 8 reviews	its 2.5 Bar which equates to roughly 36 psi

03-02-2006, 10:34 PM	#6
SoSideways Post Whore! Join Date: Apr 2003 Location: 你老母 Posts: 4,371 Trader Rating: (4) Feedback Score: 4 reviews	Yup, with vacuum line off it should be 43psi, with vacuum line on it should be 36psi. This is at idle by the way.

03-03-2006, 05:16 AM	#9
stevesr20 Join Date: Dec 2005 Location: fl Posts: 42 Trader Rating: (0) Feedback Score: 0 reviews	wow! my fp has to be at 55psi to give me a decent a/f ratio on my aem wideband (WIDEBAND NOT NARROW BAND) thats with the vac line ON... my a/f is 12.7 13.0 at 14psi. 12.5 a/f at 10psi.... wierd, can't figure out why either, (I know thats not normal) tried swapping out injectors, fuel rail, ecu, wireing harrness, and 02 sensor... all had no effect. so i bought a fpr and turned up the fuel pressure. at 43psi vac line on, my a/f was in the high 13's witch to me is lean as hell... so i turned up the fuel pressure to 53psi vac line on.... I know it's not good for the injectors, luckly i only drive it on sundays, and will be upgrading my hole fuel package soon... I am under the impression the motor and turbo are stock, but I can't figure out where all this extra air is coming from... the motor had a adjustable wga on it and a piggy back of some sort when i got it.... So the guy was a tunner. only thing i can think of is maybe a clipped turbo i dunno..... car feels strong for what it is. guess a dyno is the only way to find out. __________________ ------03' 400whp solar yellow srt-4 (R.I.P.) ------05' white srt-4 [email protected] (she is missed) ------04' HEMI quad cab 4x4 (daily driver) ------91' hatch (swapped sr20 det) ------Afghanistan (04'-05')

03-03-2006, 06:34 AM	#11
far1002 Join Date: Feb 2006 Location: gastonia,NC Posts: 11 Trader Rating: (0) Feedback Score: 0 reviews	its your fuel pump its not pumping enough fuel.

03-03-2006, 02:04 PM	#13
kuramaya Nissanaholic! Join Date: Dec 2004 Location: 沖縄 , Japan Age: 52 Posts: 1,677 Trader Rating: (1) Rides Gallery: kuramaya Feedback Score: 1 reviews	Thats weird cause I run a wideband on my car all day and night and I am at 11:1 at .9 Bar of boost with stock 370's and 3 Bar fuel pressure set with Nismo FPR and Walbro 255...something is not right... __________________ ZEROYON WEBSITE IS HOMO NEW SITE: blacklinux.com/innersanctum/index.php

03-03-2006, 02:24 PM	#14
trqless Leaky Injector Join Date: Feb 2006 Location: Winchester, VA Posts: 63 Trader Rating: (0) Feedback Score: 0 reviews	Right now my peak is 12 psi. Just got in the fpr today, about to go and put it on, hopefully it will solve my starting issues as the rail is not holding fuel, it just dumps it back into the tank after the car has been sitting.