1:1 rising rate fuel pressure - SRT Forums

Chief · 02-08-2010, 08:49 PM

JUST got my prosport electric fuel pressure on board gauge in today.. did a test drive... i run 25 psi and at idle its around 52 fuel pressure... thinking the 1:1 it would be climbing to around 75-80 psi at wot? BUT NO its only reaching like 65 range? so do the aero fpr only do .5:1 ratio when it comes to hooking the boost line up?

Just wonderin if anyone else has on board fuel pressure gauge and has seen this?

TurboTime · 02-09-2010, 08:07 AM

It could be a boost leak, how do you have the vac line to the fpr hooked up??

Chief · 02-09-2010, 09:53 AM

line from turbo to MBC than MBC over to waste gate but right at the waste gate its T'd to the fpr? DO u think since the wastegate only has 15 spring that it has somethign to do with the bleeding off of the pressure? or the mbc? i was told this is how to hook one up?

coors · 02-09-2010, 09:55 AM

Quote: Originally Posted by Chief

line from turbo to MBC than MBC over to waste gate but right at the waste gate its T'd to the fpr? DO u think since the wastegate only has 15 spring that it has somethign to do with the bleeding off of the pressure? or the mbc? i was told this is how to hook one up?

well thats why your mbc is bleeding it off, hook it somewhere else

mahkis · 02-09-2010, 10:02 AM

^x2

the fpr should be t'd before the mbc. compressor housing>fpr>mbc>wg

duster360 · 02-09-2010, 11:36 AM

Quote: Originally Posted by Chief

JUST got my prosport electric fuel pressure on board gauge in today.. did a test drive... i run 25 psi and at idle its around 52 fuel pressure... thinking the 1:1 it would be climbing to around 75-80 psi at wot? BUT NO its only reaching like 65 range? so do the aero fpr only do .5:1 ratio when it comes to hooking the boost line up?

Just wonderin if anyone else has on board fuel pressure gauge and has seen this?

Its probably the MBC bleeding boost but be aware: Low pressure Walbro 255s top out at around 68psi.
A lot of retailers sell the cheap LP version.

Chief · 02-09-2010, 01:31 PM

Quote: Originally Posted by duster360

Its probably the MBC bleeding boost but be aware: Low pressure Walbro 255s top out at around 68psi.
A lot of retailers sell the cheap LP version.

I got a 255 HP MODED pump shes good till 85 psi

BUt YES!!! this is what im thinking too... that the pressure AFTER mbc is NOT real boost OVBIOUSLY because thats its job to bleed the pressure in the line to the wastegate. SOOO i guess i need to T into the line from turbo to mbc... and the line from mbc to wastegate should be a soild line.

BUT i really dont need that kinda fuel lol im already trying to LEAN her out

so may just leave it the way it is, guess it will ALWAYS only push a extra 15 psi or so being hooked up after mbc.

BrandynSRT · 02-09-2010, 01:46 PM

why didn't you hook it up to the coldside pipe?

Chief · 02-09-2010, 01:50 PM

because we dont want the FPR to see vac. even on the charge pipe i do think there would be SOME vac pressure. not as much as AFTER the TB but im sure theres some. the ONLY true boost source is right of the turbo housing.

nutz · 02-09-2010, 01:59 PM

Quote: Originally Posted by Chief

because we dont want the FPR to see vac. even on the charge pipe i do think there would be SOME vac pressure. not as much as AFTER the TB but im sure theres some. the ONLY true boost source is right of the turbo housing.

anything pre TB will be fine, even the biggest turbos will not see vac before the TB, just make sure you have a good BOV (synapse ftw)

I would use a dedicated vacume line for the FPR (not T'd into any thing)

Chief · 02-09-2010, 02:16 PM

Quote: Originally Posted by nutz

anything pre TB will be fine, even the biggest turbos will not see vac before the TB, just make sure you have a good BOV (synapse ftw)

I would use a dedicated vacume line for the FPR (not T'd into any thing)

Well maybe ill dedicate a day to do that. Run a line directly from turbo to mbc to waste gate.. than i DO have a nipple that i can add on my charge pipe for the FPR so that would be one solid line. JEZZ more fuel

and a month ago i through i needed 044 pump

I always thought charge pipes still saw vac though? the turbo is pullin air in... if u put your hand near or around the intake of the turbo its SUCKIN pretty hard

I would think that would cause issues with the FPR?

TurboTime · 02-09-2010, 04:17 PM

JUST try to run it off the coldside pipe thats how i have mine and it seems to be fine

BrandynSRT · 02-09-2010, 04:18 PM

im going to run mine of the coldside with a check valve

Chief · 02-09-2010, 04:24 PM

idk what im gonna do yet, but i gonna do something...

i need some vac line though i ran out

Doin billet shift selector tonight FUN fun

SpeedEuphoria · 02-10-2010, 09:16 AM

vac only occurs before the throttle plate

thats why my meth never gets sucked out and its mounted in the charge pipe

02-08-2010, 08:49 PM	#1 (permalink)
Chief SRTforums Member Join Date: Feb 2008 Member Number: 61336 Location: pa Posts: 6,201	1:1 rising rate fuel pressure JUST got my prosport electric fuel pressure on board gauge in today.. did a test drive... i run 25 psi and at idle its around 52 fuel pressure... thinking the 1:1 it would be climbing to around 75-80 psi at wot? BUT NO its only reaching like 65 range? so do the aero fpr only do .5:1 ratio when it comes to hooking the boost line up? Just wonderin if anyone else has on board fuel pressure gauge and has seen this? __________________ Built HTA 60 -CoRn EaTEr- "Shes hunting unsuspecting Evo's and Sti's in their natural environment..."

02-09-2010, 09:53 AM	#3 (permalink)
Chief SRTforums Member Join Date: Feb 2008 Member Number: 61336 Location: pa Posts: 6,201	line from turbo to MBC than MBC over to waste gate but right at the waste gate its T'd to the fpr? DO u think since the wastegate only has 15 spring that it has somethign to do with the bleeding off of the pressure? or the mbc? i was told this is how to hook one up? __________________ Built HTA 60 -CoRn EaTEr- "Shes hunting unsuspecting Evo's and Sti's in their natural environment..."

02-09-2010, 09:55 AM	#4 (permalink)
coors SRTforums Member Join Date: Jun 2006 Member Number: 43166 Location: sanangelo,texas Posts: 15,637	Quote: Originally Posted by Chief line from turbo to MBC than MBC over to waste gate but right at the waste gate its T'd to the fpr? DO u think since the wastegate only has 15 spring that it has somethign to do with the bleeding off of the pressure? or the mbc? i was told this is how to hook one up? well thats why your mbc is bleeding it off, hook it somewhere else __________________ DEVILSOWN 405-470-4356 any questions pm me

02-09-2010, 11:36 AM	#6 (permalink)
duster360 SRTforums Member Join Date: Aug 2006 Member Number: 45182 Location: Central IL Posts: 5,632	Quote: Originally Posted by Chief JUST got my prosport electric fuel pressure on board gauge in today.. did a test drive... i run 25 psi and at idle its around 52 fuel pressure... thinking the 1:1 it would be climbing to around 75-80 psi at wot? BUT NO its only reaching like 65 range? so do the aero fpr only do .5:1 ratio when it comes to hooking the boost line up? Just wonderin if anyone else has on board fuel pressure gauge and has seen this? Its probably the MBC bleeding boost but be aware: Low pressure Walbro 255s top out at around 68psi. A lot of retailers sell the cheap LP version. __________________ "Just because someone goes fast doesn't mean you should do whatever you think they did. This path assumes they knew what they were doing, which isn't necessarily the case"..........RB Racing TDS is the best choice for ALL your CMR Tuning.

02-09-2010, 01:31 PM	#7 (permalink)
Chief SRTforums Member Join Date: Feb 2008 Member Number: 61336 Location: pa Posts: 6,201	Quote: Originally Posted by duster360 Its probably the MBC bleeding boost but be aware: Low pressure Walbro 255s top out at around 68psi. A lot of retailers sell the cheap LP version. I got a 255 HP MODED pump shes good till 85 psi BUt YES!!! this is what im thinking too... that the pressure AFTER mbc is NOT real boost OVBIOUSLY because thats its job to bleed the pressure in the line to the wastegate. SOOO i guess i need to T into the line from turbo to mbc... and the line from mbc to wastegate should be a soild line. BUT i really dont need that kinda fuel lol im already trying to LEAN her out so may just leave it the way it is, guess it will ALWAYS only push a extra 15 psi or so being hooked up after mbc. __________________ Built HTA 60 -CoRn EaTEr- "Shes hunting unsuspecting Evo's and Sti's in their natural environment..."

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02-09-2010, 08:07 AM	#2 (permalink)
TurboTime SRTforums Member Join Date: Apr 2005 Member Number: 26187 Location: TEXAS Posts: 285	It could be a boost leak, how do you have the vac line to the fpr hooked up??

02-09-2010, 10:02 AM	#5 (permalink)
mahkis SRTforums Member Join Date: May 2005 Member Number: 28019 Location: ... Posts: 886	^x2 the fpr should be t'd before the mbc. compressor housing>fpr>mbc>wg

02-09-2010, 01:46 PM	#8 (permalink)
BrandynSRT SRTforums Member Join Date: Apr 2008 Member Number: 63412 Location: nh Posts: 2,160	why didn't you hook it up to the coldside pipe?

02-09-2010, 01:50 PM	#9 (permalink)
Chief SRTforums Member Join Date: Feb 2008 Member Number: 61336 Location: pa Posts: 6,201	because we dont want the FPR to see vac. even on the charge pipe i do think there would be SOME vac pressure. not as much as AFTER the TB but im sure theres some. the ONLY true boost source is right of the turbo housing. __________________ Built HTA 60 -CoRn EaTEr- "Shes hunting unsuspecting Evo's and Sti's in their natural environment..."

02-09-2010, 01:59 PM	#10 (permalink)
nutz SRTforums Member Join Date: May 2006 Member Number: 41700 Location: IB, Ca. Posts: 11,229	Quote: Originally Posted by Chief because we dont want the FPR to see vac. even on the charge pipe i do think there would be SOME vac pressure. not as much as AFTER the TB but im sure theres some. the ONLY true boost source is right of the turbo housing. anything pre TB will be fine, even the biggest turbos will not see vac before the TB, just make sure you have a good BOV (synapse ftw) I would use a dedicated vacume line for the FPR (not T'd into any thing)

02-09-2010, 02:16 PM	#11 (permalink)
Chief SRTforums Member Join Date: Feb 2008 Member Number: 61336 Location: pa Posts: 6,201	Quote: Originally Posted by nutz anything pre TB will be fine, even the biggest turbos will not see vac before the TB, just make sure you have a good BOV (synapse ftw) I would use a dedicated vacume line for the FPR (not T'd into any thing) Well maybe ill dedicate a day to do that. Run a line directly from turbo to mbc to waste gate.. than i DO have a nipple that i can add on my charge pipe for the FPR so that would be one solid line. JEZZ more fuel and a month ago i through i needed 044 pump I always thought charge pipes still saw vac though? the turbo is pullin air in... if u put your hand near or around the intake of the turbo its SUCKIN pretty hard I would think that would cause issues with the FPR? __________________ Built HTA 60 -CoRn EaTEr- "Shes hunting unsuspecting Evo's and Sti's in their natural environment..."

02-09-2010, 04:17 PM	#12 (permalink)
TurboTime SRTforums Member Join Date: Apr 2005 Member Number: 26187 Location: TEXAS Posts: 285	JUST try to run it off the coldside pipe thats how i have mine and it seems to be fine

02-09-2010, 04:18 PM	#13 (permalink)
BrandynSRT SRTforums Member Join Date: Apr 2008 Member Number: 63412 Location: nh Posts: 2,160	im going to run mine of the coldside with a check valve

02-09-2010, 04:24 PM	#14 (permalink)
Chief SRTforums Member Join Date: Feb 2008 Member Number: 61336 Location: pa Posts: 6,201	idk what im gonna do yet, but i gonna do something... i need some vac line though i ran out Doin billet shift selector tonight FUN fun __________________ Built HTA 60 -CoRn EaTEr- "Shes hunting unsuspecting Evo's and Sti's in their natural environment..."

02-10-2010, 09:16 AM	#15 (permalink)
SpeedEuphoria SRTforums Member Join Date: Jul 2005 Member Number: 30870 Location: Elsewhere Posts: 1,624	vac only occurs before the throttle plate thats why my meth never gets sucked out and its mounted in the charge pipe __________________ Catch me at Sunoco, show me that your loco, put 110 in your 4 doe!! Soon the 2.4Turbo Spirit will run!!! 10's that is Project log pics http://forums.neons.org/viewtopic.ph...603&highlight= http://www.cardomain.com/ride/2641801

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