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Old Dec 30, 2001 | 04:49 PM
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Nos fuel pressure question

All questions refer to a dry kit - Can someone explain to me in detail how the the fuel pressure is raised, I know it has something with the vacume lines, but if someone could give me details that would be great. Next say your fuel pressure is 40psi at WOT and when your spraying you need it to be 80psi so you use whatever size jet you would need to get it to 80psi, but would this be bumping the psi up an addition 40 psi to get it to 80psi, or would it make the systen run at 80psi regardless of what the cars N/A fuel pressure normally is? Thanks in advance
Old Dec 30, 2001 | 08:38 PM
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ok.. you turn on your bottle.. that sends Nitrous to the door of the first solenoid.. once you activate the system and the system is engaged.. the nitrous flows between the first and second solenoid.. but inbetween them is the Nitrous Pressure Regulator which is connected via hose to the stock Fuel Pressure regulator.. once the Nitrous flows through the first solenoid and the Nitrous Pressure regulator gets that reading.. it sends the pressure to the Stock Fuel Pressure regulator and that raises the pressure.. the amount of fuel the engine gets and the amount of pressure will be determined by the Fuel Jet.. now that you are running 100 shot.. you will need a fuel jet of .069 i think it is.. Synki can confirm.. pm synki and ask him what fuel jet he is running.. when you are running 50/60/70 shot.. you use the .042 jet.. if you use that with 100 shot.. you will be running way too rich.. and may lock up your injectors..

now the reason the car doesn't run at 80 PSI during normal operation is because the Nitrous Pressure Regulator is not getting any pressure to cause the Fuel Pressure Regulator to increase Pressure.. with the Walbro 255 High Pressure pump.. you are idle at 35 PSI and WOT at 50 - 60 PSI
Old Dec 30, 2001 | 09:05 PM
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Originally posted by SprintMax
ok.. you turn on your bottle.. that sends Nitrous to the door of the first solenoid.. once you activate the system and the system is engaged.. the nitrous flows between the first and second solenoid.. but inbetween them is the Nitrous Pressure Regulator which is connected via hose to the stock Fuel Pressure regulator.. once the Nitrous flows through the first solenoid and the Nitrous Pressure regulator gets that reading.. it sends the pressure to the Stock Fuel Pressure regulator and that raises the pressure.. the amount of fuel the engine gets and the amount of pressure will be determined by the Fuel Jet.. now that you are running 100 shot.. you will need a fuel jet of .069 i think it is.. Synki can confirm.. pm synki and ask him what fuel jet he is running.. when you are running 50/60/70 shot.. you use the .042 jet.. if you use that with 100 shot.. you will be running way too rich.. and may lock up your injectors..

now the reason the car doesn't run at 80 PSI during normal operation is because the Nitrous Pressure Regulator is not getting any pressure to cause the Fuel Pressure Regulator to increase Pressure.. with the Walbro 255 High Pressure pump.. you are idle at 35 PSI and WOT at 50 - 60 PSI

for real??
Old Dec 30, 2001 | 09:09 PM
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Originally posted by sx7r



for real??
i think so
Old Dec 30, 2001 | 09:10 PM
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For 100 shot i am running a .071 jet. I am running about 85psi on 100 shot w/ that fuel jet. I am going to try a .69 jet to lean it out a bit and increase the HP. I just hope it wont run that lean.

With the 255lph fuel pump, i idle @ 39psi and @ WOT (NA) i am about 45-50psi. Its running rich b/c i am still using the stock fuel pressure regulator. The FPG is suppose to adjust itself from teh ECU but cant due to the higher flowing fuel pump. The ECU wasnt tuned to handle that much fuel. That is why it runs rich. You will need to disconnect the OEM FPR and get a Universal one and use that. You will have to adjust the universal fuel pressure manually. This will fix the idle and WOT psi (NA). The fuet jet is the only way to adjust your fuel pressure when you spray. That fuel jet will not effect your fuel pressure when NA (doesnt matter if your on stock pump or high flow pump).

Like Sprint said, use a .042 jet for 5, 60, & 70 shot.

I think normal idle is suppose to be 33-34psi. WOT you should be about 43-45psi.
Old Dec 30, 2001 | 09:14 PM
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Originally posted by Synki
For 100 shot i am running a .071 jet. I am running about 85psi on 100 shot w/ that fuel jet. I am going to try a .69 jet to lean it out a bit and increase the HP. I just hope it wont run that lean.

With the 255lph fuel pump, i idle @ 39psi and @ WOT (NA) i am about 45-50psi. Its running rich b/c i am still using the stock fuel pressure regulator. The FPG is suppose to adjust itself from teh ECU but cant due to the higher flowing fuel pump. The ECU wasnt tuned to handle that much fuel. That is why it runs rich. You will need to disconnect the OEM FPR and get a Universal one and use that. You will have to adjust the universal fuel pressure manually. This will fix the idle and WOT psi (NA). The fuet jet is the only way to adjust your fuel pressure when you spray. That fuel jet will not effect your fuel pressure when NA (doesnt matter if your on stock pump or high flow pump).

Like Sprint said, use a .042 jet for 5, 60, & 70 shot.

I think normal idle is suppose to be 33-34psi. WOT you should be about 43-45psi.
when i was on a 100shot, i found that no jet in the bypass tee worked well. but that's just me.
Old Dec 30, 2001 | 09:15 PM
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Originally posted by sx7r


when i was on a 100shot, i found that no jet in the bypass tee worked well. but that's just me.
but you are crazy.. anyone who runs 2000 PSI bottle pressure is just crazy
Old Dec 30, 2001 | 09:16 PM
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Originally posted by SprintMax
anyone who runs 2000 PSI bottle pressure is just crazy
Old Dec 30, 2001 | 09:19 PM
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Originally posted by Synki


you're off, it was 2500psi
Old Dec 30, 2001 | 09:20 PM
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Originally posted by sx7r


you're off, it was 2500psi
Great Scotts!!!
Old Dec 30, 2001 | 09:21 PM
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Originally posted by Synki


Great Scotts!!!
holy smokes!
Old Dec 30, 2001 | 09:22 PM
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i ran the kit he is trying to install at 1100-1200 all the time.
Old Dec 30, 2001 | 09:23 PM
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Originally posted by sx7r


holy smokes!
Holy Popcorn Thomas!
Old Dec 30, 2001 | 09:23 PM
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Originally posted by dmbmaxima88
i ran the kit he is trying to install at 1100-1200 all the time.
that's all? amatuer.
Old Dec 30, 2001 | 09:25 PM
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Originally posted by Synki


Holy Popcorn Thomas!
great googily moogily!
Old Dec 30, 2001 | 09:26 PM
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Holy Counter Stinkies
Old Dec 30, 2001 | 09:27 PM
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thomas it will be enough when i come thomas hunting in september.
Old Dec 30, 2001 | 09:29 PM
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Originally posted by dmbmaxima88
thomas it will be enough when i come thomas hunting in september.
can't wait. that gives you 9 months to learn how to drive that 6spd
Old Dec 30, 2001 | 09:32 PM
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Originally posted by sx7r


can't wait. that gives you 9 months to learn how to drive that 6spd
i can drive it fine now. it gives me 9 months to proto type more parts and install my NOS
Old Dec 30, 2001 | 09:35 PM
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Originally posted by dmbmaxima88


i can drive it fine now. it gives me 9 months to proto type more parts and install my NOS
slowpoke
Old Dec 30, 2001 | 09:36 PM
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Originally posted by SprintMax
Holy Counter Stinkies


You mean Counter Sprites v1.3.
Old Dec 30, 2001 | 09:39 PM
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Originally posted by Synki




You mean Counter Sprites v1.3.

yes spritemaxes
Old Dec 30, 2001 | 09:40 PM
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Originally posted by Synki




You mean Counter Sprites v1.3.
good comeback..

steve.. let us leave the future talk out of it.. just do something and surpise people.. lets leave out this "Civic Talk" .. when i get my turbo kit yo.. i will be running 9's.. see what i mean?
Old Dec 30, 2001 | 09:41 PM
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Originally posted by sx7r


great googily moogily!
Holy Frankencar!
Old Dec 30, 2001 | 09:42 PM
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Originally posted by SprintMax
good comeback..

steve.. let us leave the future talk out of it.. just do something and surpise people.. lets leave out this "Civic Talk" .. when i get my turbo kit yo.. i will be running 9's.. see what i mean?

Old Dec 30, 2001 | 09:45 PM
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Originally posted by Synki


Holy Frankencar!
frankencar performance products inc.

and sprint, i hear ya.
Old Dec 30, 2001 | 09:47 PM
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Originally posted by dmbmaxima88


frankencar performance products inc.

is there a website?
Old Dec 30, 2001 | 09:53 PM
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Originally posted by sx7r


is there a website?
no just a thread for now.. we shall keep you updated
Old Dec 30, 2001 | 09:56 PM
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Originally posted by Synki




You mean Counter Sprites v1.3.
I wanna play!!!
Old Dec 31, 2001 | 01:35 AM
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Originally posted by SprintMax
ok.. you turn on your bottle.. that sends Nitrous to the door of the first solenoid.. once you activate the system and the system is engaged.. the nitrous flows between the first and second solenoid.. but inbetween them is the Nitrous Pressure Regulator which is connected via hose to the stock Fuel Pressure regulator.. once the Nitrous flows through the first solenoid and the Nitrous Pressure regulator gets that reading.. it sends the pressure to the Stock Fuel Pressure regulator and that raises the pressure.. the amount of fuel the engine gets and the amount of pressure will be determined by the Fuel Jet.. now that you are running 100 shot.. you will need a fuel jet of .069 i think it is.. Synki can confirm.. pm synki and ask him what fuel jet he is running.. when you are running 50/60/70 shot.. you use the .042 jet.. if you use that with 100 shot.. you will be running way too rich.. and may lock up your injectors..

now the reason the car doesn't run at 80 PSI during normal operation is because the Nitrous Pressure Regulator is not getting any pressure to cause the Fuel Pressure Regulator to increase Pressure.. with the Walbro 255 High Pressure pump.. you are idle at 35 PSI and WOT at 50 - 60 PSI
Thanks Sprint that helps out a lot ,now say your running a 100 shot and you need fuel pressure to be around 85-90 psi so you use the .69 jet, and your car runs at 45psi at wot, that would mean the nitrous pressure regulator is increasing psi by 40-45 psi. Now lets just say for some reason your car ran 75psi at wot, would running the same .69 fuel jet still increase psi by 40-45 bringing your psi up to 115-120psi, or would it bring the psi up to 85-90 psi like it did when your car was 45psi at wot?
Old Dec 31, 2001 | 02:26 AM
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if your car is running at 75 PSI at WOT.. you need to get that looked at.. thats way too rich.. you might have 02 sensors blown or something..

if that was the case.. you wold do a run with the 100 shot.. notice the car was running way too rich.. then increase the Fuel Jet size to lean it out to 80 - 85 PSI

Originally posted by CoOlKidS1979


Thanks Sprint that helps out a lot ,now say your running a 100 shot and you need fuel pressure to be around 85-90 psi so you use the .69 jet, and your car runs at 45psi at wot, that would mean the nitrous pressure regulator is increasing psi by 40-45 psi. Now lets just say for some reason your car ran 75psi at wot, would running the same .69 fuel jet still increase psi by 40-45 bringing your psi up to 115-120psi, or would it bring the psi up to 85-90 psi like it did when your car was 45psi at wot?
Old Dec 31, 2001 | 04:52 AM
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Originally posted by SprintMax
no just a thread for now.. we shall keep you updated
yuup yup. tank u sprint. i'm gonna register i website for it soon. either www.frankencar.com or www.frankencarperformance.com which one you think?????
Old Dec 31, 2001 | 04:59 AM
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Originally posted by dmbmaxima88

[url]www.frankencarperformance.com[/url
Old Dec 31, 2001 | 09:45 AM
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The first time I ran mine with the new fuel pump I was over 100psi of fuel pressure...
Old Dec 31, 2001 | 11:04 AM
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Originally posted by SprintMax
if your car is running at 75 PSI at WOT.. you need to get that looked at.. thats way too rich.. you might have 02 sensors blown or something..

if that was the case.. you wold do a run with the 100 shot.. notice the car was running way too rich.. then increase the Fuel Jet size to lean it out to 80 - 85 PSI

Im not saying that my car runs at 75psi, I was just saying that as an example, what I was tring to ask is this, say your car runs at 40 psi and the nitrous pressure regulator increases it by 40 psi so now you have 80 psi, which is a 40 psi increase. Now say that your car ran at 60 psi instead of the 40 psi, and you then used the same sized jet would it still incrrease the psi by 40 psi as it did when the car was running at 40psi, or would it still only increase it to 80 psi.
Old Dec 31, 2001 | 11:08 AM
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Originally posted by CoOlKidS1979


Im not saying that my car runs at 75psi, I was just saying that as an example, what I was tring to ask is this, say your car runs at 40 psi and the nitrous pressure regulator increases it by 40 psi so now you have 80 psi, which is a 40 psi increase. Now say that your car ran at 60 psi instead of the 40 psi, and you then used the same sized jet would it still incrrease the psi by 40 psi as it did when the car was running at 40psi, or would it still only increase it to 80 psi.
to best of my knowledge.. synki and i run different FP at WOT.. .. but we still round off to 80 - 85 PSI on 100 shot.. i don't understand the skematics and the underling of it.. maybe Matt or Thomas could explain futher.. but i don't think its a 40 PSI increase by the regulator.. i think the regulator will determind a FP by the amount of pressure and with the Stock FPR... which means.. say if you did run 65 PSI at WOT.. with the same fuel jet as stynki and myself.. you would still be at 80 - 85 PSI.. not by a constant PSI increase..
Old Dec 31, 2001 | 11:29 AM
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When you go to an aftermarket FPR the bypass jets will be slightly different than what was needed for a factory FPR. I never ran a 100 shot on a factory FPR, too scarey for my blood.

In theory, if your running 75psi at WOT you would need 45psi more to do a 100 shot through factory 4g injectors. I allways stay on the safe side of theory and work my way down. Just remember you need 4x the pressure to get twice the flow through the same size injector. For a 200 shot you would need 45(base fp)+45(first100hp)+90(second 100hp)=180 psi. Kids, dont try this at home

If you are running 75psi at NA/WOT u got a problem!
Old Dec 31, 2001 | 11:32 AM
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Originally posted by MardiGrasMax
When you go to an aftermarket FPR the bypass jets will be slightly different than what was needed for a factory FPR. I never ran a 100 shot on a factory FPR, too scarey for my blood.

In theory, if your running 75psi at WOT you would need 45psi more to do a 100 shot through factory 4g injectors. I allways stay on the safe side of theory and work my way down. Just remember you need 4x the pressure to get twice the flow through the same size injector. For a 200 shot you would need 45(base fp)+45(first100hp)+90(second 100hp)=180 psi. Kids, dont try this at home

If you are running 75psi at NA/WOT u got a problem!
and "the man" has spoken..
Old Dec 31, 2001 | 01:35 PM
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Originally posted by SprintMax
and "the man" has spoken..
But can he answer my question from 4 posts back?????
Old Dec 31, 2001 | 02:51 PM
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Originally posted by CoOlKidS1979


But can he answer my question from 4 posts back?????
why? i already answered it

maybe if you ask the question directly.. and tell us what you are trying to find out we can answer it.. asking hypothetical questions is going to get you generic answers



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