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Anyone find a fix for fuel sloshing and starvation?

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Might be a good time to look into a racing fuel cell. These units work great in both every day drivers and track only dedicated vehicles. Race Safe and ATL are a couple of manufacturers that immediately come to mind. I have a Race Safe installed in a track dedicated 97' cobra that handles fuel delivery nicely on the long high speed sweepers at Willow Springs. Look for a cell that is SFI and/or FIA certified. Racing cells are also much safer in track environments. The folks at the previously mentioned outfits should have a solution for your application. Good luck in your search
Correction: the first manufacturer is Fuel Safe not Race Safe!
 
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Yes my symptoms went away after a fill up but returned after 2 runs, which was about a half tank.
Does the track make any difference? I saw "Mission" and it's not famous for grip, particularly at this time of year, especially when it's cold like it has been. Area 27 in July will be a bigger test, presuming you're going. Big fast corners and lots of grip - that's a real test.
 
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FWIW and this is a huge overkill, the Phoenix cars used a custom cell and as many as 4 pumps in the main/surge tanks when we ran IMSA. I've seen local guys have good results with the fuel mat, but as mentioned, it needs to be nailed down somehow. The surge tank seems like a reasonable alternative however.
 
75
91
Exp. Type
HPDE
Exp. Level
5-10 Years
Langley, BC
I am running the stock module at the moment with all the nannies turned off. I have felt the stability system activating before and it's definently not that. This was more of a bucking/surging of the motor and also when it did it on corner exit I could see the afr's shoot up into the 16:1 range which is not good at wide open throttle. I have the aux pump coming in tomorrow and have all the other things I need to hopefully come up with a fix and I will see how this works next run. I am very surprised that your car didn't have any issues that day, are you on the stock pump? These pumps can be taxed out between supplying the engine and syphoning the fuel from the other tank as well.
Yep stock pump. I haven't felt the issues yet.
 
These are all good suggestions. I will try what I had planned initially and see how viable that is. Its a pretty low cost test and if it doesnt help at all I will most likely look into a surge tank. The fuel hat assemblies look like a nice option but suspect that they may still have issues as others have said. I got all my parts for the project im going to try but have to go to work for 4 days now and wont be able to do it until after.

Does the track make any difference? I saw "Mission" and it's not famous for grip, particularly at this time of year, especially when it's cold like it has been. Area 27 in July will be a bigger test, presuming you're going. Big fast corners and lots of grip - that's a real test.

It also does it at The Ridge and havent been to area 27 yet. I wanted to go in July but its sold out. I may put myself on the waiting list and hope for the best. Mission is heavy on left turns thats why I think I have issues. It may be my OEM pump is on its way out as well and not able to supply enough fuel to the engine and also act as a siphon as 80KM2E had no issues on the same day.
 
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These are all good suggestions. I will try what I had planned initially and see how viable that is. Its a pretty low cost test and if it doesnt help at all I will most likely look into a surge tank. The fuel hat assemblies look like a nice option but suspect that they may still have issues as others have said. I got all my parts for the project im going to try but have to go to work for 4 days now and wont be able to do it until after.



It also does it at The Ridge and havent been to area 27 yet. I wanted to go in July but its sold out. I may put myself on the waiting list and hope for the best. Mission is heavy on left turns thats why I think I have issues. It may be my OEM pump is on its way out as well and not able to supply enough fuel to the engine and also act as a siphon as 80KM2E had no issues on the same day.
I think something weird is going on in your car somewhere. I did the Ridge and Mission many times, first in a 2011 Mustang GT and then in a 2014 GT500 and I didn't have any fuel starvation problems with either one, even down below a 1/2 tank. It doesn't make sense how sensitive your car seems to be to it.
 
I think something weird is going on in your car somewhere. I did the Ridge and Mission many times, first in a 2011 Mustang GT and then in a 2014 GT500 and I didn't have any fuel starvation problems with either one, even down below a 1/2 tank. It doesn't make sense how sensitive your car seems to be to it.


Yeah it's definently strange and annoying. Could also be differences in tires and driving style. What tires did you run when you didn't have issues?
 
The gt500 has dual pumps in the basket, obviously for fuel demands of that supercharger but it helps take the load off the one pump for siphoning from the passenger side tank. The gt350 also has dual pumps, those guys don't seem to complain much about this issue also.
 
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The gt500 has dual pumps in the basket, obviously for fuel demands of that supercharger but it helps take the load off the one pump for siphoning from the passenger side tank. The gt350 also has dual pumps, those guys don't seem to complain much about this issue also.
That's correct - I've run my GT350 down to 1/4 tank without a problem at the Ridge.
 
$750 for the GT500 dual pump setup beats $2500 for the surge tank. Just sayin'.

Yeah the only problem is that on the GT they use a mechanical fuel pressure regulator in the basket and a 2 speed control system, high and low. On the gt500 there is no regulator that I can see, I think they use a more sophisticated control system through the ecm and fuel pump module to vary the pumps output to whatever pressure they need. I guess an external regulator can be made to work in this scenario.
 
Yeah the only problem is that on the GT they use a mechanical fuel pressure regulator in the basket and a 2 speed control system, high and low. On the gt500 there is no regulator that I can see, I think they use a more sophisticated control system through the ecm and fuel pump module to vary the pumps output to whatever pressure they need. I guess an external regulator can be made to work in this scenario.
AdmirC, so the solution is to just get the gt500 dual pump setup but that actually wont work in the Boss? or in my std. S197 due to the ECM not supporting it / the mechanical setup on the Boss? Do you know of a work around? 2500 for a surge is a lot, and changing to a fuel Cell will not negate the need for a surge (did you see the last Cleetus Mcfarland where they had to add a surge to the Dale truck? ) I wonder if there is an adapter type kit.. hmm.. Also i'm assuming all of this stuff can be just dropped in from the hat. :(
 
AdmirC, so the solution is to just get the gt500 dual pump setup but that actually wont work in the Boss? or in my std. S197 due to the ECM not supporting it / the mechanical setup on the Boss? Do you know of a work around? 2500 for a surge is a lot, and changing to a fuel Cell will not negate the need for a surge (did you see the last Cleetus Mcfarland where they had to add a surge to the Dale truck? ) I wonder if there is an adapter type kit.. hmm.. Also i'm assuming all of this stuff can be just dropped in from the hat. :(

Yes the gt500 dual pump will physically drop in but will need an external regulator to work properly as the ECM on the gt500 controls the fuel pressure. What I think will work and what the BMW guys do as well is put another oem fuel pump assembly in the passenger side tank. 2 options after this, you can route the flow of that pump into the basket of the main pump to feed it so to speak and keep it primed, you could do this with an in tank line directly off the second pump, which is what I'm going to try to do with a simpler version to prove the concept. Or, you can T both pumps and use the pressure output of these to feed the engine. This involves more lines and etc but should be a good mod and I may look into this if the above fails. Also if you were to T in both pumps you would have to add another fuel pump control module to control the second pump so you retain the high low voltage feature that our cars have. That's why I chose the feeder style system due to the simplicity and not having to add another module. Track day is on the 21st of July, will test to see if the feeder pump will work and make a better system.
 
Yes the gt500 dual pump will physically drop in but will need an external regulator to work properly as the ECM on the gt500 controls the fuel pressure. What I think will work and what the BMW guys do as well is put another oem fuel pump assembly in the passenger side tank. 2 options after this, you can route the flow of that pump into the basket of the main pump to feed it so to speak and keep it primed, you could do this with an in tank line directly off the second pump, which is what I'm going to try to do with a simpler version to prove the concept. Or, you can T both pumps and use the pressure output of these to feed the engine. This involves more lines and etc but should be a good mod and I may look into this if the above fails. Also if you were to T in both pumps you would have to add another fuel pump control module to control the second pump so you retain the high low voltage feature that our cars have. That's why I chose the feeder style system due to the simplicity and not having to add another module. Track day is on the 21st of July, will test to see if the feeder pump will work and make a better system.

excellent idea and i cant wait for the track report! im tempted to just buy the s197 gt500 setup and try to use the existing power and controls to directly fire both those pumps simultaniously as if it were just the single factory 9one..
 
So first off let me start by saying I'm in no way saying this is the best way to do this, I am just trying out something that was relatively inexpensive to see if it would give me positive results. Modify your fuel system at your own risk. Also, I would like to give ford a big middle finger...they were nice enough to make holes inside the body for fuel pump access but not nice enough to make them a little bigger than the locking rings for the pumps. The tank still has to be dropped by an inch or so just to be able to slide the lock rings sideways above the tank to get the pump modules out. The locking rings will not come out from the top! That being said this is what I did. First off, I removed the passenger side level sender assembly and the main fuel pump assembly on the drivers side. I mounted the Carter fuel pump to the level sender assembly stem with stainless steel worm gear clamps. Make sure you clear the level sender arm and also the siphon tube attachment nipple.
Then I drilled 2 holes on top of the hat to screw in machine screws that I cut the heads off to make them studs on both ends, also secured by a washer and a nut on both ends. These holes were fit so that the screws were tight enought that they had to be screwed in making threads and also sealed with a washer and nut further sealing the assembly. I was going to add fuel safe silicone to the washers but I'm very confident in how tight the screws were inside the holes and the nuts further providing clamping force to seal that it was not needed. These will be used to wire the new fuel pump.
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Then I mounted nylon fuel hose to the assembly and routed it. Well this turned out to be a complete pain as this hose is too rigid and will not work. It kinks very easily and is impossible to work with.20200624_133714.jpg
Regular fuel line hose will not work as the outer shell will degrade in fuel. Submersible fuel hose is very expensive at 25 bucks a foot. I talked to a hose company near me called Newline hose and they had small engine fuel hose made from polyurethane that was fuel resistant and could be submersed. It does not handle pressure but since there is no load on this pump just flow it will work great for my needs. The hose is blue and it's 5/16 in size.
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I ran this hose from one side of the tank to another. Attached it to the secondary fuel pump and placed everything inside the passenger side tank. Don't forget to attach the siphon tube to the unit and make sure everything will clear. Then I routed the internal hose to point into the main pump hat just to the side of the main pump to fill the basket with fuel. This is a mock-up still with the nylon hose.
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I secured the hose to the metal guide that is part of the assembly with another stainless worm gear clamp about half way up so that it can still compress when installed.
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Then install the main pump and connect the other end of the siphon tube to it. Fish the new hose to it and attach it to the clamp shown above.
This is very tricky to do and the pic is not clear but the hose is secured and it is pointing straight down beside the main pump into the cavity of the pump. This took lots of time to make sure it was routed properly and clear of the level sensor arm. Mounted everything up and resecured the tank. Next I ran a 12 gauge wire through a Honeywell 1TL13 on off switch rated for 20 amps. I was going to relay the power source but I will fuse the system at 15 amps. This will be safe for the switch and should be enough current for the small Honda fuel pump. I ran the wire through the grommet on the drivers side, as you can see I have my sub and my oil temp sensor already through it. Ran it up by the master cylinder and to the battery through a fuse. Wrap everything in conduit under the hood to give it a nice look. Also, I zip tied the switch to the harness under the dash which is hidden but can be reached from the seat. It was also sturdy enough to operate and saved me from drilling a hole for the switch.
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Route the wire along the sill and to the new fuel pump. Went through the existing grommet on the fuel pump cover and attached to the precious studs that I made. Grounded it to a bolt on the removable side plate on the B pillar.

Part numbers for parts used:
-Carter fuel pump P74223HP
-Auto best connector FW801 ( used this as it was thicker gauge than the supplied connector that came with the Carter pump.)
-NL5570031047 5/16 polyurethane fuel hose
-Honeywell 1TL13 on/off switch

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Next track day is July 21st. That will be the test. Again, please modify your fuel system at your own risk. Know that there is a high risk of fire if attempting this due to volatile gasoline being exposed. I am not liable if you burn your car, house or yourself down.
 
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Yeah the only problem is that on the GT they use a mechanical fuel pressure regulator in the basket and a 2 speed control system, high and low. On the gt500 there is no regulator that I can see, I think they use a more sophisticated control system through the ecm and fuel pump module to vary the pumps output to whatever pressure they need. I guess an external regulator can be made to work in this scenario.

i swapped to gt500 pumps only thing i had to do was wire in a second fuel pump driver. tuner took care of the rest. ive not had any issues with fuel starvation on track yet. granted ive only got a few events on the new setup but it hasnt been an issue yet. ive run it down to below 1/4 tank at hallet.
 
i swapped to gt500 pumps only thing i had to do was wire in a second fuel pump driver. tuner took care of the rest. ive not had any issues with fuel starvation on track yet. granted ive only got a few events on the new setup but it hasnt been an issue yet. ive run it down to below 1/4 tank at hallet.

Was your tuner able to control the fuel pressure from the PCM then? That may be the way to go as it's not hard to wire in another driver and split the output from the PCM for the control.
 

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