Tuning Ford returnless fuel system

[robert presti]

I'm working on a new tune. The car has twin 450 lph fuel pumps. I can't select these as an option in Advantage 3 software. The fuel pressure is wicked erratic and wonder if anyone has built a table that gets them working right. I have way to much fuel pressure at idle and not enough when revving it. Fluctuations are more so than with the old pumps at a steady speed

 

[ClubVenom1]

Need more info on fuel system components and type of car. Do you have a BAP/single FPDM? Dual FPDM's? Upgraded wiring to FPDM's. A lot can play a role in this.

Are the pumps new. If so are they for the returnless system and not a return system. This can cause an issue. Is the FPDM going into safe mode due to current draw from the pumps?
If the pumps are the correct ones for a returnless, and your not going into LIMP mode in the FPDM due to over heating the curcuits, then i would start looking at your FRPS. That is what adjusts fuel pressure for the injectors. It could be faulty.

 

[robert presti]

I don't know about the pumps they are the walbro f90000267 . Some people say they will work some say not. The car had 2 focus pumps with a cobra hat and one fuel pump driver module . Now the car has two drivers so there is one for each pump. One driver is wired as a slave. The fuel rail pressure sensor is the same and should be good. This fuel pressure issue is because of the pumps I just installed. I don't have an amp clamp so I'm not positive both pumps are working. I installed a division x fuel hat so if worst came to worse I'd just run a return line.

There are two things in Advantage 3 software to help stabilize fuel pressure. There is also a base table of voltages for the pumps that can be adjusted. I just have no idea where to start and haven't found much information on it. I have a fuel pressure gauge and it was always around 21 at idle, now I'm at 30. I should have paid attention to the vacuum gauge, but it was always around 17 in the past. The tune is calling for 40 psi, same as the last tune on the old pumps with 21 psi at idle. With the old set up you would get a pound or two of variation.

The car is a 2000 mustang.

 

[ClubVenom1]

Fore Innovations lists those pumps for return service fuel systems and not returnless. I would follow the pro's advice and make it a return system if I were you. Otherwise get the Walbro F10000302 which are the improved GT pumps 250lph and are for the returnless system in your car. Use that with a BAP. Whats your goals that you need so much fuel?

 

[robert presti]

Fore Innovations lists those pumps for return service fuel systems and not returnless. I would follow the pro's advice and make it a return system if I were you. Otherwise get the Walbro F10000302 which are the improved GT pumps 250lph and are for the returnless system in your car. Use that with a BAP. Whats your goals that you need so much fuel?

The goal was 750 wheel on E85. but that might not happen now. The other thought was if I lost one fuel pump at alternator voltage I would still have enough fuel. If I lost an alternator and had two pumps working I'd be good.

The car made over 600whp and ran out of fuel at 21 lbs of boost.

 

[04sleeper]

Yeah, those pumps are not set up for returnless systems.

The NEW GT Pumps in a Fore Hat, BAP set to 50, Dual FPDM's, Wiring Upgrade, -8 fuel line and ID1000's should get you 750 on Corn.

 

[ClubVenom1]

Nice goal.... I would go return system if I were you. There is a 720 rwhp E85 whipple cobra that is on the returnless system but it's vamped up, bigger wire, dual FPDM's, GT pumps, BAP, etc.... (Nevermind 04sleeper beat me to it.)Why you worried about loosing a pump on returnless? I run a 03 cobra/whipple at 18psi and have upgraded wire, BAP, Single stock FPDM, stock pumps and i never once worried about loosing a pump. Plus I tune using SCT PRP too. Been running it like this since 2007. 600rwhp. Are you centri/turbo/PD blower?

 

[robert presti]

Nice goal.... I would go return system if I were you. There is a 720 rwhp E85 whipple cobra that is on the returnless system but it's vamped up, bigger wire, dual FPDM's, GT pumps, BAP, etc.... (Nevermind 04sleeper beat me to it.)Why you worried about loosing a pump on returnless? I run a 03 cobra/whipple at 18psi and have upgraded wire, BAP, Single stock FPDM, stock pumps and i never once worried about loosing a pump. Plus I tune using SCT PRP too. Been running it like this since 2007. 600rwhp. Are you centri/turbo/PD blower?

I have a D1 Procharger with an air to air intercooler. This is a ported 2 valve with bigger valves and bigger cams. Iron block, cobra crank and h-beam rods. The car is at around 17psi but something in the tune had it hitting a rev limit at 5600 or so. The car dynode at 605 with 21psi at 6200. I don't know if the pulley was changed or if I get it revving to that again I'll find the missing boost. Static compression ratio of 8.5. I went big on the fuel because it might get a bigger engine in the future.

 

[robert presti]

Yeah, those pumps are not set up for returnless systems.

The NEW GT Pumps in a Fore Hat, BAP set to 50, Dual FPDM's, Wiring Upgrade, -8 fuel line and ID1000's should get you 750 on Corn.

I'm not going to run a boost a pump. At this point if the car can't be tuned to maintain fuel pressure I'll add a regulator and go return fuel. I just thought I'd try the pumps and someone said they could work returnless, but the tables need work. I have an -8 fuel line and 80 lbs injectors. I don't know how many times I'll try to guess as what the table should look like, before I give up.

 

[04sleeper]

I have never heard of anyone running those pumps in a returnless setup. But when dialing in the FPVT, you will need to build the table by logging about 45 different PID's. Half at a time with Key On Engine Off and program them into the voltage table based on your log.

 

[robert presti]

I have never heard of anyone running those pumps in a returnless setup. But when dialing in the FPVT, you will need to build the table by logging about 45 different PID's. Half at a time with Key On Engine Off and program them into the voltage table based on your log.

I get what your saying after looking around a little bit. The fuel pumps can be pulse width modulated, which I thought meant for running returnless, but have check valves that won't release the pressure if it spikes. I'm thinking of running a regulator near the tank to bleed off the pressure spikes. Not sure this is the best way to deal with the situation, but If the pumps are always fat it would mean less circulated fuel if they are somewhat speed controlled rather than just running them 100% with a large return line.
'

I'm assuming you meant to say returnless not return in your post.