Fuel Pressure Regulator
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From: Tulsa, Oklahoma
Fuel Pressure Regulator
Guys,
Who has done it?? Any install help/advice?? Best brand?? etc Do you have to run new fuel lines? Return line??? Anyone??
Thanks,
Jonny
Who has done it?? Any install help/advice?? Best brand?? etc Do you have to run new fuel lines? Return line??? Anyone??
Thanks,
Jonny
What are you trying to achieve by adding a regulator?
Edit... read your sig a little more closely and I remember a prior post about a dyno running too lean? Looks like you have a Walbro 255 pump in your tank and larger capacity injectors. You don't think you are getting enough fuel into your engine? From my recollection the regulator will only make sure the fuel pressure will not exceed a certain PSI (create a ceiling), not work to meet a minimum (create a floor)...
Edit again... if you think you need more fuel ask your tuner about a fuel management unit to help with leveling out your AFR. The FMU will add fuel as needed, based on some measurement like boost or RPM level.
Edit... read your sig a little more closely and I remember a prior post about a dyno running too lean? Looks like you have a Walbro 255 pump in your tank and larger capacity injectors. You don't think you are getting enough fuel into your engine? From my recollection the regulator will only make sure the fuel pressure will not exceed a certain PSI (create a ceiling), not work to meet a minimum (create a floor)...
Edit again... if you think you need more fuel ask your tuner about a fuel management unit to help with leveling out your AFR. The FMU will add fuel as needed, based on some measurement like boost or RPM level.
Last edited by ShadyJC; Dec 5, 2005 at 10:21 AM.
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From: Tulsa, Oklahoma
Originally Posted by ShadyJC
What are you trying to achieve by adding a regulator?
Edit... read your sig a little more closely and I remember a prior post about a dyno running too lean? Looks like you have a Walbro 255 pump in your tank and larger capacity injectors. You don't think you are getting enough fuel into your engine? From my recollection the regulator will only make sure the fuel pressure will not exceed a certain PSI (create a ceiling), not work to meet a minimum (create a floor)...
Edit again... if you think you need more fuel ask your tuner about a fuel management unit to help with leveling out your AFR. The FMU will add fuel as needed, based on some measurement like boost or RPM level.
Edit... read your sig a little more closely and I remember a prior post about a dyno running too lean? Looks like you have a Walbro 255 pump in your tank and larger capacity injectors. You don't think you are getting enough fuel into your engine? From my recollection the regulator will only make sure the fuel pressure will not exceed a certain PSI (create a ceiling), not work to meet a minimum (create a floor)...
Edit again... if you think you need more fuel ask your tuner about a fuel management unit to help with leveling out your AFR. The FMU will add fuel as needed, based on some measurement like boost or RPM level.
Jonny
Originally Posted by Dx3
Guys,
Who has done it?? Any install help/advice?? Best brand?? etc Do you have to run new fuel lines? Return line??? Anyone??
Thanks,
Jonny
Who has done it?? Any install help/advice?? Best brand?? etc Do you have to run new fuel lines? Return line??? Anyone??
Thanks,
Jonny
) As for brand, not exactly sure but I know my shop pulled it off a BMW. Aeromotive is one of the more popular brands that most go with. Now with my just recently installed 2.62" pulley we're finding I now have to up my injectors from my current 310's because I'm not getting near enough fuel up top- that's currently being worked out and hopefully I'll have a full write-up in the next couple of weeks that will include my impressions of the JB Headers as well 
Last edited by Dr.G; Dec 7, 2005 at 09:34 PM.
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From: 808state
I have decided to go with the SX/Aeromotive fuel pressure regulator. (both are made by the same company just labled differently) You need to make a return line. I don't really like the stock setup as it is just a blind/dead end. I would rather that the fuel flow through the whole rail and then be regulated after the injectors and not before. With the FPR at the fuel rail, it will ensure that the pressure is always where it needs to be. You will need to defeat the regulator at the pump since this is where the stock system controls the pressure in the fuel line. I feel more comfortable with this and tuning seems to be pretty easy when your fuel pressure is constant. No need to worry if the FMU (these units will raise the fuel pressure 1:1, that is 1lb more pressure per 1lb boost) is not working correctly. You will know if the pressure is there or not.
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From: Tulsa, Oklahoma
Originally Posted by Dr.G
Jonny- I had to add a FPR and Walbro pump to solve my lean conditions when I dropped to the 2.87" pulley from the 3.125". (FYI-pump was added first , tuned again, wasn't enough, added FPR ) As for brand, not exactly sure but I know my shop pulled it off a BMW. Aeromotive is one of the more popular brands that most go with. Now with my just recently installed 2.62" pulley we're finding I now have to up my injectors from my current 310's because I'm not getting near enough fuel up top- that's currently being worked out and hopefully I'll have a full write-up in the next couple of weeks that will include my impressions of the JB Headers as well
) As for brand, not exactly sure but I know my shop pulled it off a BMW. Aeromotive is one of the more popular brands that most go with. Now with my just recently installed 2.62" pulley we're finding I now have to up my injectors from my current 310's because I'm not getting near enough fuel up top- that's currently being worked out and hopefully I'll have a full write-up in the next couple of weeks that will include my impressions of the JB Headers as well So do you know much about your FPR?? Please tell me what you do know about it. Is it working?? Do you know what the pressure is compared to stock??
HI98GS - check PM.
Thx guys,
Jonny
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Lead Lap
Joined: Nov 2004
Posts: 441
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From: Alberta
Originally Posted by HI98GS
I have decided to go with the SX/Aeromotive fuel pressure regulator. (both are made by the same company just labled differently) You need to make a return line. I don't really like the stock setup as it is just a blind/dead end. I would rather that the fuel flow through the whole rail and then be regulated after the injectors and not before. With the FPR at the fuel rail, it will ensure that the pressure is always where it needs to be. You will need to defeat the regulator at the pump since this is where the stock system controls the pressure in the fuel line. I feel more comfortable with this and tuning seems to be pretty easy when your fuel pressure is constant. No need to worry if the FMU (these units will raise the fuel pressure 1:1, that is 1lb more pressure per 1lb boost) is not working correctly. You will know if the pressure is there or not.
I had aeromotive in my 240, and it kicked ***. It never fluctuated even when it got super cold where I live to hot dry heat temperatures. Once I set it I never had to touch it again. That was from a greddy FPR guage that installed nicely on the FPR as it has a sensor port.
The aeromotive gives you instructions on how to install it. On my 240 it was installed after the injectors and fuel rail.
This one.
http://216.242.145.16/products/product.phtml?p=10
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Thread Starter
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From: Tulsa, Oklahoma
Originally Posted by Hollywood
Thx man,
Jonny
Lexus Test Driver
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From: 808state
If you look at the stock fuel pump, you will see that there is a return outlet near it. this is the one that needs to be bypassed since you will need to have all the fuel go to the fuel rail and the excess drained back to the tank. The stock system does not do this as it just keeps the pressure constant at the pump thinking that this will keep the whole pressure constant at the rail. Fuel will only flow from the tank into the injectors but there could be a block along the way that may hinder the flow of fuel to the rails. if you look at this video and look at the fuel lines.
http://videos.streetfire.net/Player....5FB0148D73&p=0
http://videos.streetfire.net/Player....5FB0148D73&p=0
specific questions about the return line
I considered starting a new thread but this one seems to already be a good start on what I need.
Specific questions are as follows.
1. how do you get the stock psi regulator out of the tank, does anyone have pics of the tank?
2. The rest seems pretty straight forward disconnect the fuel line from the rail and put the regulator in place then screw the output to the rail.
3. hook up vacume line
4. hook up PSI guage
5. drill and tap the tank for a #6 AN line. Use a B nut on the inside of the tank to secure the fitting. I'm told that you can stick your arm in the tank and screw down the Bnut on the fitting. Is this true?
5. hook up return line on both ends
6. Stop at Homedepot for Fire extinguisher.
Pix of the tank and psi regulator would be helpful.
Specific questions are as follows.
1. how do you get the stock psi regulator out of the tank, does anyone have pics of the tank?
2. The rest seems pretty straight forward disconnect the fuel line from the rail and put the regulator in place then screw the output to the rail.
3. hook up vacume line
4. hook up PSI guage
5. drill and tap the tank for a #6 AN line. Use a B nut on the inside of the tank to secure the fitting. I'm told that you can stick your arm in the tank and screw down the Bnut on the fitting. Is this true?
5. hook up return line on both ends
6. Stop at Homedepot for Fire extinguisher.
Pix of the tank and psi regulator would be helpful.
Pole Position
Joined: Nov 2005
Posts: 365
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From: Florida
I have been in the tank and there is a few suprises..........
1. the regulator is in the tank so it re circulates right in the tank and there is no fuel line from the motor back
2.when you put your aftermarket pump in you will need to make another whole for the return and a return line.
3. best yet there is a tricky valve that utilizes the return pressure to create a siphoning effect to keep fuel even in both tanks (hump in the floor) If not you can only fill it up half way and just when you thought lexus was slacking the GS has two sensors one on each side so it will throw a low fuel light even though you just put in 20 bucks in(on one side.)
1. the regulator is in the tank so it re circulates right in the tank and there is no fuel line from the motor back
2.when you put your aftermarket pump in you will need to make another whole for the return and a return line.
3. best yet there is a tricky valve that utilizes the return pressure to create a siphoning effect to keep fuel even in both tanks (hump in the floor) If not you can only fill it up half way and just when you thought lexus was slacking the GS has two sensors one on each side so it will throw a low fuel light even though you just put in 20 bucks in(on one side.)
Thread Starter
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From: Tulsa, Oklahoma
Originally Posted by morris
are you talking about a gs400? There is no stock return line in that?
Jonny