Fuel pressure reg. question.
Thread Starter
Racer
Joined: Nov 2000
Posts: 268
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From: Tyler, TX.
Fuel pressure reg. question.
I was looking at the regulator on my LT-4 and it has a set screw in the top of it. Do the stock ones have this or do i have an adjustable one and didn't know it?? It's a silver body with some letters and numbers stamped in the top with a allen head bolt in the top of it. Let me know what you think.
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Re: Fuel pressure reg. question. (N20LT4)
Sounds adjustable to me! Get a fuel pressure guage, hook it up, and turn the screw. Watch the pressure change!
Thread Starter
Racer
Joined: Nov 2000
Posts: 268
Likes: 0
From: Tyler, TX.
Re: Fuel pressure reg. question. (Marcho Polo)
I'm at work and can't check it with a gauge unfortuntaly. I have been trying to get an adjustable one for a while to compensate for when i put my 255l high pressure pump in. Never bothered to look at what i had already.... Just wanted to see what all the other LT-4 car's regulators look like. Dang, just order an Aeromotive one yesterday!!!
Race Director
Joined: May 2001
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Re: Fuel pressure reg. question. (N20LT4)
If you have an extra one I might be interested, depending on the price.
It all kinda depends on how much money I get Friday. I haven't been paid in a while (messed up paperwork, isn't working for the University wonderful?) My first priority will be the MSD digital 6 ignition box, but if I have some more money I might be interested in your regulator. If it's the same on a 92? I know they have changed the fuel rails a little since 92.
It all kinda depends on how much money I get Friday. I haven't been paid in a while (messed up paperwork, isn't working for the University wonderful?) My first priority will be the MSD digital 6 ignition box, but if I have some more money I might be interested in your regulator. If it's the same on a 92? I know they have changed the fuel rails a little since 92.
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Thread Starter
Racer
Joined: Nov 2000
Posts: 268
Likes: 0
From: Tyler, TX.
Re: Fuel pressure reg. question. (Nathan Plemons)
I've got one that i won't be using. It is the Accel version that you take your existing one and convert it to and adjustable top. It should work fine since you are using the bottom of your existing regulator. I paid $40 plus shipping. Let me know if you want it and i will sell it to you for that.
Advanced
Joined: Aug 2001
Posts: 74
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Re: Fuel pressure reg. question. (N20LT4)
I've got a quick question about my 87's L98 (its my first Corvette and I've owned it about 1 month now):
I know the previous owner put in a different fuel pressure regulator; what are the benefits (and disadvantages if any)? Does the PROM need to be switched out to a custom one in order to take advantage of the new regulator?
I know the previous owner put in a different fuel pressure regulator; what are the benefits (and disadvantages if any)? Does the PROM need to be switched out to a custom one in order to take advantage of the new regulator?
Safety Car
Joined: Mar 2000
Posts: 3,620
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From: Hillsboro OR
Re: Fuel pressure reg. question. (N20LT4)
I'm at work and can't check it with a gauge unfortuntaly. I have been trying to get an adjustable one for a while to compensate for when i put my 255l high pressure pump in. Never bothered to look at what i had already.... Just wanted to see what all the other LT-4 car's regulators look like. Dang, just order an Aeromotive one yesterday!!!
Drifting
Joined: Jun 1999
Posts: 1,272
Likes: 0
From: South Carolina
Re: Fuel pressure reg. question. (N20LT4)
Jon,
Not to change the subject, but I'm curious as to what N2O kit you're using? I'm thinking of doing this to mine, and I'm interested in numbers and pictures of installs. Anything you could send my way would be appreciated. Thanks. :seeya
Not to change the subject, but I'm curious as to what N2O kit you're using? I'm thinking of doing this to mine, and I'm interested in numbers and pictures of installs. Anything you could send my way would be appreciated. Thanks. :seeya
Burning Brakes
Joined: Aug 2000
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From: Warrenville IL
Re: Fuel pressure reg. question. (Eric94)
Jon, I don't know what kit you're using but I was at the track with Mike (MVR155) a couple weeks ago after he installed his 255ltr pump. He has a NOS dry system on his car. The car ran fine NA but as soon as the nitrous kicked on it would kill his engine, the fuel pressure would peg the gauge at 100-110psi and lock up the injectors.
He needed to change to a larger jet size, very large in the T fitting going to the regulator to compensate for the extra fuel pressure in the lines from the pump.
He needed to change to a larger jet size, very large in the T fitting going to the regulator to compensate for the extra fuel pressure in the lines from the pump.
Melting Slicks
Joined: Jun 2001
Posts: 2,525
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From: Sarasota, FL
Re: Fuel pressure reg. question. (Dutch W.)
I've got a quick question about my 87's L98 (its my first Corvette and I've owned it about 1 month now):
I know the previous owner put in a different fuel pressure regulator; what are the benefits (and disadvantages if any)? Does the PROM need to be switched out to a custom one in order to take advantage of the new regulator?
I know the previous owner put in a different fuel pressure regulator; what are the benefits (and disadvantages if any)? Does the PROM need to be switched out to a custom one in order to take advantage of the new regulator?
The chip does not need to be reprogrammed. By adjusting the fuel pressure you can tune yuor car for the best fuel pressure. The oxygen sensor, MAF etc all talk to your ecm regarding how much air is going into your engine and how much air is coming out (CO, Unburned gas, etc) and the ecm adjusts the duration of the fuel pulse from the injector. The best way to tune with pressure regualtor is with time slips at a drag strip, or witha scan tool that can tell you what your exhaust etc, looks like. Spark plug reading can also help tell you if your engine is running rich or lean.
Bob
Thread Starter
Racer
Joined: Nov 2000
Posts: 268
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From: Tyler, TX.
Re: Fuel pressure reg. question. (BobMachus)
Well i figured the high volume pump would push more than the stock regulator could bypass and the pressure would come up. I could easily be wrong....
Eric94, i'm using a NX single nozzle before the throttle body. It's the generic EFI kit that they sell for lots of EFI cars. I am running the 150 poopie with an MSD and haven't had a single problem with detonation or anything. I am getting the bigger pump for insurance. I will try to get some picks for you and send them your way.
Eric94, i'm using a NX single nozzle before the throttle body. It's the generic EFI kit that they sell for lots of EFI cars. I am running the 150 poopie with an MSD and haven't had a single problem with detonation or anything. I am getting the bigger pump for insurance. I will try to get some picks for you and send them your way.
Le Mans Master
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Re: Fuel pressure reg. question. (BobMachus)
BOB,
Or anybody, I thought the chip needs progamming to get best results AFPR? I assume now that there is no data sent to the ecm regarding the fuel pressure? I did'nt install one when I had my chip done so I'm going by hear-say. How often does the AFPR setting need to be checked? TIA.
-John
Or anybody, I thought the chip needs progamming to get best results AFPR? I assume now that there is no data sent to the ecm regarding the fuel pressure? I did'nt install one when I had my chip done so I'm going by hear-say. How often does the AFPR setting need to be checked? TIA.
-John
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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
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Re: Fuel pressure reg. question. (N20LT4)
I still using the stock tank fuel pump and I also don't have a adjustable fuel pressure regulator. Cartek set everything to feed the 30lbs injectors through the PCM. Don't waste your money till your making alot more HP.
Advanced
Joined: Aug 2001
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Re: Fuel pressure reg. question. (mackeyred96)
My '87 coupe that I bought 5 weeks ago already has an AFPR (other than that, the car is stock except its K&N air filter, modified air filter lid and RapidFire sparkplugs); is the AFPR doing anything or has the ECM cancelled it out?
I'm getting an intermittent code 44 (too lean); could adjusting the AFPR be the answer? Its running pretty well, but takes 2 tries to start it or a touch of gas during the 1st start up.
I'm getting an intermittent code 44 (too lean); could adjusting the AFPR be the answer? Its running pretty well, but takes 2 tries to start it or a touch of gas during the 1st start up.
