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Discussion Starter #1
i was running 35-36 psi but bumped it to 39 psi and it feels better but still don't know how much to turn it up ! just wondering what other people are running with good times !
 

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I RUN MINE AT 39-40 PSI.........
 

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Discussion Starter #4
anywhere between 40-45
even with the 255 pump ! my car doesn't seem to like it, it started surging pretty bad @ 39-40, but i think my 02's are on the way out ! i ran the car and it felt better....... i'll have to do some testing this friday at the track hoping to get low 12's @ 110-112 out of it this time.
 

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I run my car at 38-39ish with no problems and my car's pretty stock; check the sig. With your combo you should definitly be running mid 12's at least.. Up the fuel pressure and good luck.
 

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On my old combo (302, E-Cam, 24#'s, A9P, No tune) I ran 39#. AFR was 15 at idle and 12.9 through the lights. The car ran low 12.80's
 

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damn i have a 255 fuel pump and 24lbs inj. and if a were to run 38-39 of fuel psi. my car would feel weak. i would have to run the pressure up to 50psi with the vacuum line disconnected just so i could get 43-44 psi
 

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Discussion Starter #8
damn i have a 255 fuel pump and 24lbs inj. and if a were to run 38-39 of fuel psi. my car would feel weak. i would have to run the pressure up to 50psi with the vacuum line disconnected just so i could get 43-44 psi
i believe everyone is talking about with the vac line disconnected ! i hope ?
 

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That is the right way to adjust your fuel pressure right?? Adjust it with the vac line disconnected then reconnect it and the fuel pressure should drop a bit. Mine dropped like 1 that's it.
 

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Discussion Starter #10
That is the right way to adjust your fuel pressure right?? Adjust it with the vac line disconnected then reconnect it and the fuel pressure should drop a bit. Mine dropped like 1 that's it.
You have a bad regulator !
 

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Discussion Starter #11
damn i have a 255 fuel pump and 24lbs inj. and if a were to run 38-39 of fuel psi. my car would feel weak. i would have to run the pressure up to 50psi with the vacuum line disconnected just so i could get 43-44 psi
so you are running 50 with the vac line off and 43-44 with it on ?
 

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Discussion Starter #13
That is the right way to adjust your fuel pressure right?? Adjust it with the vac line disconnected then reconnect it and the fuel pressure should drop a bit. Mine dropped like 1 that's it.
if your fuel pressure isn't dropping more than 1 psi when you reconnect vac to your fpr then its bad ! it should lower it about 6-8 psi maybe more maybe less but definatly more than 1 psi !
 

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LoL OK !

Thanks for the info. How would I know if it's affecting me performance wise?? Would the car kind of sputter or lag at WOT?? It does that like once a month or so for like half a second then doesn't do it again for about another month lol no clue what it could be.
 

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Discussion Starter #17
i ran 30-32 na and 38-42 on the jug... 24's 190lph and stock lines and rails.... on the bottle the plugs read just a touch rich...
is that with the vac off or on !
 

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Do people STILL think changing fuel pressure will do anything?

unless you have disabled the adaptive strategy you are wasting your time.
 

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Discussion Starter #19
Do people STILL think changing fuel pressure will do anything?

unless you have disabled the adaptive strategy you are wasting your time.
yeah it does but it will adapt to a point ! and changing the psi mainly effects wide open performance. because then the ecu can't adapt because the o2's quit reading. my car has a surge at idle and the only way to get it to go away is to lower my psi and clock my c&l meter, which is probobly caused by bad o2's ! but changing fuel pressure does help......
 

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sorry.......all closed loop fuel trims are used to determine open loop (WOT) pulse widths.

And if you adjust past adaptive you better have a wide band or you really won't know what you have done.

And if you have a wide band, why wouldn't you have a tuner and do it right.
 
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