adjustable fuel psi regulator need some pointers
#1
adjustable fuel psi regulator need some pointers
hey guys wanna know which fuel pressure regulator is every1 running on? im lookin at the fuel lab 1 and aem 1.. are they all the same?? thanks
#3
#8
#11
It depends on how the kit is designed.
P-tuning uses a plug because they modify the sending unit as little as possible. Instead of giving you an improved feed line they have you cut the stock plastic line off the feed fitting from the sending unit, re-use the sending unit fitting and hose clamp a braided line onto the fitting you removed from the stock line ( i do not think this is safe, that is my opinion i would feel much better with an AN fitting) and then plug the regulator port so that you can use the feed solely as a feed line. Then you run the return into the sending unit and use the original feel line as your return line.
The only issues I have with doing something like this is that you don't actually get a full bolt on kit. If you ever want to return to stock or have to for some reason (ie state inspection, selling the car, trading in) you would have to go buy a new line from the dealer to fix the problem.
Another issue is using the stock feed port to supply fuel to the upgraded kit. The size of the feed on the stock sending unit is .2110" inner diameter which is roughly 7/32" allowed for the feed. You would see improvements if you used a -6an feed which is .375" or 3/8" continuous. The benefits of this would be less strain on the fuel pump which means less amperage draw and overall more output from your in tank fuel pump. Taking this attention to detail often times makes needing a second fuel pump unnecessary. If you upgraded the fuel feed side you would have to add a fuel filter inline but that is easy and what most people do anyhow. The stock fuel filter is super restrictive and with good cause as it was designed to flow enough fuel to make 200 hp. The factory fuel filter is located inside the sending unit and is not replaceable. I think this is stupid because if that filter plugs up you have to replace a $250 sending unit as opposed to a $12 dollar filter.
Not to mention if you look at where the FPR goes in the sending unit you will notice a passage to the filter media. That O ring on the stock sending unit prevents fuel from bypassing out of that cavity. The pump fills that cavity where the fuel filter resides before it leaves the sending unit. By removing the stock FPR completely you are allowing pumped fuel to bleed back to the tank. If it were that easy do you think that P tuning would have taken the time to make a plug?
The only way you can get around removing the plug completely is if you do not use the stock fuel filter and instead use a hose to connect directly from the fuel pump to the feed fitting you would have to add.
I have designed a sending unit that utilizes this and thus does not require a fuel plug. Any other way would cause problems. Maybe not something you would see at lower boost but higher boost for sure in the way of fuel starvation.
These statements are not meant to be antagonistic in any way shape or form. This is factual data, minus my opinions. Please take it as such.
P-tuning uses a plug because they modify the sending unit as little as possible. Instead of giving you an improved feed line they have you cut the stock plastic line off the feed fitting from the sending unit, re-use the sending unit fitting and hose clamp a braided line onto the fitting you removed from the stock line ( i do not think this is safe, that is my opinion i would feel much better with an AN fitting) and then plug the regulator port so that you can use the feed solely as a feed line. Then you run the return into the sending unit and use the original feel line as your return line.
The only issues I have with doing something like this is that you don't actually get a full bolt on kit. If you ever want to return to stock or have to for some reason (ie state inspection, selling the car, trading in) you would have to go buy a new line from the dealer to fix the problem.
Another issue is using the stock feed port to supply fuel to the upgraded kit. The size of the feed on the stock sending unit is .2110" inner diameter which is roughly 7/32" allowed for the feed. You would see improvements if you used a -6an feed which is .375" or 3/8" continuous. The benefits of this would be less strain on the fuel pump which means less amperage draw and overall more output from your in tank fuel pump. Taking this attention to detail often times makes needing a second fuel pump unnecessary. If you upgraded the fuel feed side you would have to add a fuel filter inline but that is easy and what most people do anyhow. The stock fuel filter is super restrictive and with good cause as it was designed to flow enough fuel to make 200 hp. The factory fuel filter is located inside the sending unit and is not replaceable. I think this is stupid because if that filter plugs up you have to replace a $250 sending unit as opposed to a $12 dollar filter.
The only way you can get around removing the plug completely is if you do not use the stock fuel filter and instead use a hose to connect directly from the fuel pump to the feed fitting you would have to add.
I have designed a sending unit that utilizes this and thus does not require a fuel plug. Any other way would cause problems. Maybe not something you would see at lower boost but higher boost for sure in the way of fuel starvation.
These statements are not meant to be antagonistic in any way shape or form. This is factual data, minus my opinions. Please take it as such.
Last edited by DezodDon; 12-21-2009 at 04:01 PM.
#12
I think the ptuning fuel return that is out right now would be enough for most boosted tc right now.. I just installed mine and it did wonders. My 550 cc injectors are static at 6 psi on E85 and right after I installed the fuel return system with fuel pressure only set at 50psi my WOT afrs are now 8 to 10s what used to be 12.5-13 when i was on the stock system.
#13
#14
lol yeah i know what you mean. You do have a point on that tiny stock sender fitting, that maybe something they might change with their bigger fuel system w/ dual pumps.. BTW Is dezod coming up with fuel system too?
#15
#17
It depends on how the kit is designed.
Not to mention if you look at where the FPR goes in the sending unit you will notice a passage to the filter media. That O ring on the stock sending unit prevents fuel from bypassing out of that cavity. The pump fills that cavity where the fuel filter resides before it leaves the sending unit. By removing the stock FPR completely you are allowing pumped fuel to bleed back to the tank. If it were that easy do you think that P tuning would have taken the time to make a plug?
The only way you can get around removing the plug completely is if you do not use the stock fuel filter and instead use a hose to connect directly from the fuel pump to the feed fitting you would have to add.
I have designed a sending unit that utilizes this and thus does not require a fuel plug. Any other way would cause problems. Maybe not something you would see at lower boost but higher boost for sure in the way of fuel starvation.
These statements are not meant to be antagonistic in any way shape or form. This is factual data, minus my opinions. Please take it as such.
Not to mention if you look at where the FPR goes in the sending unit you will notice a passage to the filter media. That O ring on the stock sending unit prevents fuel from bypassing out of that cavity. The pump fills that cavity where the fuel filter resides before it leaves the sending unit. By removing the stock FPR completely you are allowing pumped fuel to bleed back to the tank. If it were that easy do you think that P tuning would have taken the time to make a plug?
The only way you can get around removing the plug completely is if you do not use the stock fuel filter and instead use a hose to connect directly from the fuel pump to the feed fitting you would have to add.
I have designed a sending unit that utilizes this and thus does not require a fuel plug. Any other way would cause problems. Maybe not something you would see at lower boost but higher boost for sure in the way of fuel starvation.
These statements are not meant to be antagonistic in any way shape or form. This is factual data, minus my opinions. Please take it as such.
would it have helped that i put my return line to dump into the cavity where the sending unit sits? i basically just drilled out the top of where the stock fpr was and ran my return line there......perhaps this is why my car runs lean when i turn a corner to sharp.....or maybe its because i broke the wire leading to my power steering pump
#18
ok right now im trying to do the same set up on the afpr and return line setup as yahama.. i cant tell if he drill out 2 holes for his set up on the fuel assembly.. any1 have some advice? thanks
#20
would it have helped that i put my return line to dump into the cavity where the sending unit sits? i basically just drilled out the top of where the stock fpr was and ran my return line there......perhaps this is why my car runs lean when i turn a corner to sharp.....or maybe its because i broke the wire leading to my power steering pump
The only time you can totally remove the stock FPR is when you connect a hose straight from the pump to the outlet of the sending unit and use an aftermarket fuel filter such as an aeromotive or fuel lab or whatever you get the point.
The way the stock system and the p tuning system work they still make use of the restrictive fuel filter that is built in to the sending unit which is why they need to have either the FPR or the FPR plug in it's place. Follow the path from where the pump plugs in stock to where it exits stock.
Why would breaking the wire going to your power steering pump cause you to go lean? The only thing that does is increase your idle when you turn the steering wheel to full lock to accommodate for the additional load of the excess pressure in the system. This helps prevent stalling.
Last edited by DezodDon; 12-22-2009 at 03:05 PM.