<HELP>Will running 65psi of fuel pressure on a stock LS1 damage it in any way
07-12-2004, 10:24 PM
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<HELP>Will running 65psi of fuel pressure on a stock LS1 damage it in any way I know i need 58 psi of fuel pressure to the rails on a stock motor but i am at 65 psi and shes not running very well, the tail pipe is coated in black soot and i am getting about 14 miles per gallon,
I am told by the PROS at the local stealership that at 65 psi, there is unburnt gas blowing thru and out the tail pipe and the motor is running rich. he said this is why I am getting poor gas milage and that accounts for the black soot inside the tail pipe.
He clames after i bring the pressure back down to 58psi, I will see a dramatic change in miles per gallon and she will be running the proper fuel to air ratio.
Is this BS or Is he on to something.
I am told by the PROS at the local stealership that at 65 psi, there is unburnt gas blowing thru and out the tail pipe and the motor is running rich. he said this is why I am getting poor gas milage and that accounts for the black soot inside the tail pipe.
He clames after i bring the pressure back down to 58psi, I will see a dramatic change in miles per gallon and she will be running the proper fuel to air ratio.
Is this BS or Is he on to something.
07-13-2004, 05:51 PM
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Originally Posted by slow
they are right, you need to get the fuel pressure donn to proper range, or program the comptuer for the higher pressure.
but i woudl just fix the fuel pressure.
Ryan
but i woudl just fix the fuel pressure.
Ryan
So this is the cause for my very poor gas mileage?
07-13-2004, 07:48 PM
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Originally Posted by slow
your fuel milage should pick up at least 2-3 mpg when using the correct fuel pressure.
what else do you have done, untuned, and headers by any chance? that will make even more improvement in gas milage, getting it tuned.
Ryan
what else do you have done, untuned, and headers by any chance? that will make even more improvement in gas milage, getting it tuned.
Ryan
This is a stock setup, I am the one that cramed a LS1/4L60e into a 1998 Jeep wrangler, everything works well but i'm just not sure if she is running perfect, even after I fix the fuel pressure problem (parts are on the way).
When you say TUNED, what and where is that? (sorry to sound like a dolt but I gotta ask)
I guess the best question to ask is< Should I get my setup tested because of the conversion and where can I go to do it?> (grand rapids Michigan)
I have access to LS1 edit but I'm not sure what to look for.
Thanks for all your help
Steve
07-13-2004, 08:40 PM
#7
well, since your a conversion, just a few questions to make sure everything is alright.
your fuel pressure is static correct, and not vac referenced? im assuming so, as if you vac referenced it you would not be high as you are.
What are you using for exhaust manifolds, and intake? stock maf? screened? how long is the piping in front of the maf? straight, or curved? any pics of the conversion (not necessary that they will help, but that sounds like an interesting swap (I have a 03 wrangler in the garage too)
By tuning, i mean having the computer edited to ensure a proper air fuel ratio, and proper timing. You can do this with ls1edit, but you will need some kind of scanner as well, many people use efilive, but there are others out there.
What year is your motor from, and what year is the computer? if motor is a 98, 01 or 02, with a 1999-2000 computer, then the fueling tables will be rich, as the 99-00 are 26# injector cars, and the 98, 01-02 use 28.x pound injectors. just one possibility of running rich.
And lastly, lets get to the vehicle, gear ratios, tire size, and when your driving, what kind of rpm's are you turning?
Sorry for all of the questions, but its not easy to solve problems online in this depth.
Ryan
your fuel pressure is static correct, and not vac referenced? im assuming so, as if you vac referenced it you would not be high as you are.
What are you using for exhaust manifolds, and intake? stock maf? screened? how long is the piping in front of the maf? straight, or curved? any pics of the conversion (not necessary that they will help, but that sounds like an interesting swap (I have a 03 wrangler in the garage too)
By tuning, i mean having the computer edited to ensure a proper air fuel ratio, and proper timing. You can do this with ls1edit, but you will need some kind of scanner as well, many people use efilive, but there are others out there.
What year is your motor from, and what year is the computer? if motor is a 98, 01 or 02, with a 1999-2000 computer, then the fueling tables will be rich, as the 99-00 are 26# injector cars, and the 98, 01-02 use 28.x pound injectors. just one possibility of running rich.
And lastly, lets get to the vehicle, gear ratios, tire size, and when your driving, what kind of rpm's are you turning?
Sorry for all of the questions, but its not easy to solve problems online in this depth.
Ryan
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07-13-2004, 09:43 PM
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Originally Posted by slow
well, since your a conversion, just a few questions to make sure everything is alright.
your fuel pressure is static correct, and not vac referenced? im assuming so, as if you vac referenced it you would not be high as you are.
What are you using for exhaust manifolds, and intake? stock maf? screened? how long is the piping in front of the maf? straight, or curved? any pics of the conversion (not necessary that they will help, but that sounds like an interesting swap (I have a 03 wrangler in the garage too)
By tuning, i mean having the computer edited to ensure a proper air fuel ratio, and proper timing. You can do this with ls1edit, but you will need some kind of scanner as well, many people use efilive, but there are others out there.
What year is your motor from, and what year is the computer? if motor is a 98, 01 or 02, with a 1999-2000 computer, then the fueling tables will be rich, as the 99-00 are 26# injector cars, and the 98, 01-02 use 28.x pound injectors. just one possibility of running rich.
And lastly, lets get to the vehicle, gear ratios, tire size, and when your driving, what kind of rpm's are you turning?
Sorry for all of the questions, but its not easy to solve problems online in this depth.
Ryan
your fuel pressure is static correct, and not vac referenced? im assuming so, as if you vac referenced it you would not be high as you are.
What are you using for exhaust manifolds, and intake? stock maf? screened? how long is the piping in front of the maf? straight, or curved? any pics of the conversion (not necessary that they will help, but that sounds like an interesting swap (I have a 03 wrangler in the garage too)
By tuning, i mean having the computer edited to ensure a proper air fuel ratio, and proper timing. You can do this with ls1edit, but you will need some kind of scanner as well, many people use efilive, but there are others out there.
What year is your motor from, and what year is the computer? if motor is a 98, 01 or 02, with a 1999-2000 computer, then the fueling tables will be rich, as the 99-00 are 26# injector cars, and the 98, 01-02 use 28.x pound injectors. just one possibility of running rich.
And lastly, lets get to the vehicle, gear ratios, tire size, and when your driving, what kind of rpm's are you turning?
Sorry for all of the questions, but its not easy to solve problems online in this depth.
Ryan
The motor/tranny/computer is from a 2001 TransAm with 22,000 miles. The fuel pressure was read from the fuel rail with a new fuel pressure gauge that read 65psi on the money.
my exhaust manafold is stock and comming off of that is 2.5" tube that is curved to the passanger side into a 3" Y-pipe into a 3" catco converter into a single Magnaflow 3" stainless steel straight through design muffler over the axel and out the passanger side.
I have 3.73:1 gear ratio W/ 33" BFG's turning about 1650 RPM @ 60 mpr
This was a bitch of a convertion to do but well worth it, it took about seven months to plan and gather parts and only five weeks to complete the conversion. I can get the front end off the ground but I dont like to do that too many times.
The main reason for all the concerns is my buddy has a 2000 trans am and his seems to run alot better than mine as far as responce time and torque.
I hope I drew a better picture for ya........I just want my toy to run as best as it can
Thanks
Steve
07-15-2004, 03:27 AM
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I have 3.73:1 gear ratio W/ 33" BFG's turning about 1650 RPM @ 60 mpr This would be my best guess as to why your MPG are so shitty but then again im a newbie so dont just take my opinion!
Goodluck on the fix!
Goodluck on the fix!
