Throttle cutting out in hard left turns !!!

[Competition Orange]

seems highly tire/driver/track dependent.

On 300tw summer tires, my stock engined car had zero issues at mid ohio, and I ran it down until the gas light dinged. I'll be filling up more often going forward, but just some data for this.

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[402]

I am on full suspension and slicks, I see fuel starvation between 3/4 and 1/2 tank. Just have to top off every other session. Tc/sc off.

 

[chedder]

Left hand turn pics Pacific Raceway 10/01/2016

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[Josh_TypeX]

Bumping this thread.

Myself and 3 other members were at Phillip Island (a counterclockwise circuit) on the weekend and all encountered fuel starvation in the long left hand corners. Anything close to 3/4 a tank and I started getting it.

Any solutions anyone has found other than the foam? I have someone suggest a fuel pump voltage booster, however I don't understand how this could improve the fuel starvation issue. I don't want to run a surge tank as this is my daily.

I'm curious what the difference is with the GT350 setup, I would expect if the GT350 had similar issues it would be more prevalent due to the increased grip and would be mentioned in some reviews.. I believe the GT350 runs duel pumps, however again I do not see how this would help.

Pics for attention.

 

[Wally-Bob]

Subscribed.

I haven't experienced this, have run the fuel down to almost nothing.
Maybe I haven't pulled enough Gs or the left turns weren't long enough?
Steeda progressives and sway bars but stock P-Zeros...

 

[chrisgonzales]

Resurrecting this as curious what other may have done other than the foam ran into this issue today at TGPR on a few of the left handers it's also run counterclockwise. I'm running e85. My car is a GT with mods: gt350 manifold / TB, 47lb injectors, e85 lund tune.

Ruled out all the nannies threw out the day wasted most of my session as i wasn't sure what the deal was and it kept happening with 3/4 tank. And couldn't get far after topping of the tank for every session.

Mine was demanding too much from the pump/tank with the e85 so curious what solutions are out there. I did end up putting 5 gallons of 93 end of day and getting one last session in and it helped the issue by lessening the demand on the pump

Thanks in advance

 

[thatonenozz]

 

[Plimmer]

Here is what I've noticed about our fuel tank:
There is an access hole on both sides of the tank, driver side is fuel pump and a level sender and passenger side also has a hat, but only a level sender.

It looks like you could mount a pump in there as well, so maybe someone with enough $$$ could buy another pump hat and run a pump setup on both sides. Then have the one side push fuel to the driver side and push fuel to the fuel rail.

Maybe an engineer could figure out, I still have my stock fuel hat so maybe one day I'll put in the passenger side and tap it into the main line

 

[MaverickGT]

I had this very issue this weekend along with another 2015 GT. Posted in another thread but found this one. Here's the details.

I was at the track and had the engine cut power a couple times coming out of a corner. This was the last couple laps of the session. It is a sweeping left that you hold about 15 seconds and then track out. On track out full acceleration the power cuts out momentarily and then comes back on. The turn starts slow off camber and progresses to 85-95mph at track out with 1+G. Seems like a fuel issue. At this time the tank was ½ full. This doesn’t happen when the tank is full. It took 9 gallons on fill up. Would a boost a pump resolve this? I'll be going with a Whipple in a couple weeks and don't want this happening then.

Running in track mode with traction control turned off 5secs.

 

[GJarrett]

Sub'd for the fuel cell info. Good stuff!

 

[BmacIL]

According to this the GT has dual pumps like the GT350, but the Left-hand pump is FR3Z-9H307-E for the GT350 and FR3Z-9H307-B for the GT. Right-hand pumps are the same.
https://www.tascaparts.com/auto-par...e/fuel-system-cat/fuel-system-components-scat

 

[Plimmer]

According to this the GT has dual pumps like the GT350, but the Left-hand pump is FR3Z-9H307-E for the GT350 and FR3Z-9H307-B for the GT. Right-hand pumps are the same.
https://www.tascaparts.com/auto-par...e/fuel-system-cat/fuel-system-components-scat

I knew the GT350 had 2 pumps, but didn't know that its one each side of the tank. The GT 5.0 only has 1 pump on the drivers side, thats way its sucks air in left hand turns.

I've had both sides of my tank open and can report the following:
1. Passenger side on GT is a fuel level sensor and some kind of suction tube to the drivers side.
2. There are no baffles, trap doors or gates that prevent fuel from sloshing around in the tank, so its no surprise that all the fuel ends up in the passenger side of the tank on left hand turns.

 

[BmacIL]

I knew the GT350 had 2 pumps, but didn't know that its one each side of the tank. The GT 5.0 only has 1 pump on the drivers side, thats way its sucks air in left hand turns.

I've had both sides of my tank open and can report the following:
1. Passenger side on GT is a fuel level sensor and some kind of suction tube to the drivers side.
2. There are no baffles, trap doors or gates that prevent fuel from sloshing around in the tank, so its no surprise that all the fuel ends up in the passenger side of the tank on left hand turns.

Interesting that they list two. I'll check my build BOM for my car, though it'll probably just list the whole tank assembly.

 

[Plimmer]

Interesting that they list two. I'll check my build BOM for my car, though it'll probably just list the whole tank assembly.

This is all I have in my car, no pump, just this sender, with a tube that I think leads to the driver side.

 

[ddozier]

This is all I have in my car, no pump, just this sender, with a tube that I think leads to the driver side.

GT has one electrical fuel pump in the Drivers Side, the Passenger side is a sending unit and a tube that leads to the Drivers side venturi pump that is part of the fuel pressure regulator that is built into the Drivers side fuel hat.

The system tries to keep as much fuel as possible in the drivers side of the tank, it does this by routing the bypassed fuel from the pressure regulator in the drivers side fuel hat to a venturi pump that siphons the line leading to the Passenger side sending unit.

This works fine when you are running at low RPMs and are not using all the fuel the pump can provide. The pressure regulator will divert the unneeded fuel back to the drivers side tank through a venturi system that then draws the fuel from the passenger tank into the drivers side of the tank. Run at high RPMs and keep the engines fuel demand high and there is not enough fuel being diverted to the venturi pump to draw the fuel to the drivers side, add in a left hand turn and slosh even more fuel to the passenger side and the drivers side tank will run dry.

The GT350 has 2 pumps in the Drivers side of the tank and the same venturi system to draw from the passenger side. The GT350 has twice the pump capacity but not twice the fuel needs so it will always be bypassing more fuel to keep the venturi with enough fuel to allow the siphon system to work properly. Unfortunately you can not swap in a GT350 pump in the GT without adding another fuel pump driver module and wiring it into the car.

You could run a boost-a-pump and get the same results but it is hard on the pump to increase the voltage all the time. You can do like the BMW guys do as they suffer from a similar design and add a secondary pump in the passenger side to pump the fuel over. You can also add the fuel cell foam in the hump of the tank and reduce the problem to a manageable level and keep the fuel tank at least half full. The best solution is to add a fuel surge tank or a fuel cell if you need to get every drop of fuel out of the car while tracking.

Dave

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