97MarkJA
Dedicated LVC Member
So is this the ticket? MOTORCRAFT Part # PFS204 {#3S4U9H307BB, 3S4Z9H307BC}
Tousley is right up the street from my work.
Fuel pump/pressure question
- Thread starter 97MarkJA
- Start date
So is this the ticket? MOTORCRAFT Part # PFS204 {#3S4U9H307BB, 3S4Z9H307BC}
Tousley is right up the street from my work.
97MarkJA
Dedicated LVC Member
97 and 98 are the same... or at least my 97 is the same as my dads 98.
Laser tried to put a gas tank on his old 97 that was from a 98 and there were differences, maybe the evap canister fittings? I don't remember.
97MarkJA
Dedicated LVC Member
In searching for info on the FPDM I found that the 97/98 used the same FPDM as all the 98-04 mustangs. The part number is different on the moduals only because of the bracket attached to it, the modual itself is the same even though the 97/98 Mark and 98 Mustang use a return style fuel system and the 99 > is returnless.
DLF posted some great info above and I found a little more on a fuel pump site that goes a little deeper.
98-04 Mustang Technical Background
Prior to January 2011, we didn't list a high performance 255 LPH fuel pump for the 1998 and later Ford Mustang. Some companies will sell you the same kit used on the 96-97 Cobra, but there are a list of reasons why you should consider this option very carefully.
The '98 and later Mustangs do not use a standard mechanical-style fuel pressure regulator. Instead, the computer senses the fuel pressure and controls it by sending a "pulse wave modulated" (PWM) signal to the fuel pump. To simplify, this means that it alters the voltage to control the pressure output by the fuel pump. This works well with many turbine-style fuel pumps, but the Walbro 255 LPH fuel pumps are gearotor-style. The low voltages that PWM-controlled systems generate cause them to start "cogging", which can result in reduced pump longevity. One solution to this would be to simply install a 12 VDC power to the fuel pump, switched to "on" when the key is in the on or start position, then add a mechanical fuel pressure regulator. This disables the cability of the ECU to control the fuel pressure (which is considered by most to be a positive feature.)
Assuming that the installation of a switched 12 VDC power supply to the fuel pump was done correctly (and ignoring the obvious safety considerations of failing to do that,) there are yet other issues to consider. The 98+ Mustang's fuel pump sits down in a resevoir that holds the fuel around the pickup during cornering. That is not unusual. However, the resevoir for the 98+ Mustang is shorter, vertically, than that of the 96-97 Cobra, so the fuel pump does not fit into that resevoir as well. If you overcome that issue, then there is the fact that the Walbro fuel pump can quickly out-flow the jets that allow fuel to flow into the resevoir. This means that, at a high-fuel useage situation in a heavily modified Mustang, starvation could occur, particularly at lower fuel levels when passive filling (fuel running over the sides of and into the resevoir) is not available. One solution that has been developed to this problem is to drill holes in the resevoir to allow additional fuel to flow into the resevoir. However, this is not an all-positive solution, as this also allows fuel to run out of the resevoir, effectively limiting the fuel baffling purpose for which it was designed.
The right answer? Unfortunately, until Walbro released their 255 LPH High Performance Walbro fuel pump that fits properly into this application (mentioned at the top of this article) there wasn't one. The Walbro OE-replacement TCA903 turbine-style pump provides roughly 180 liters per hour of fuel at the standandard 45 psi / 12 vdc that the unit sees in an unmodified Mustang. 180lph is conservatively capable of fueling 470 naturally-aspirated horsepower--380 if the horsepower is turbo- or supercharger produced. Now, if you're sure that you need more fuel then the new 255 LPH 98-04 Mustang Fuel Pump can provide, then we have another alternative for you. We highly recommend the Fore Precision Fuel Hat, which allows you to install two PWM-style fuel pumps side-by-side in the fuel tank. Alternatively, for such a high-performance requirement, consider having an aftermarket fuel cell installed in the car. This will allow you to use something like the Walbro 255 LPH inline fuel pump that is available from Fuel-Pumps.Net, along with a mechanical fuel pressure regulator.
DLF posted some great info above and I found a little more on a fuel pump site that goes a little deeper.
98-04 Mustang Technical Background
Prior to January 2011, we didn't list a high performance 255 LPH fuel pump for the 1998 and later Ford Mustang. Some companies will sell you the same kit used on the 96-97 Cobra, but there are a list of reasons why you should consider this option very carefully.
The '98 and later Mustangs do not use a standard mechanical-style fuel pressure regulator. Instead, the computer senses the fuel pressure and controls it by sending a "pulse wave modulated" (PWM) signal to the fuel pump. To simplify, this means that it alters the voltage to control the pressure output by the fuel pump. This works well with many turbine-style fuel pumps, but the Walbro 255 LPH fuel pumps are gearotor-style. The low voltages that PWM-controlled systems generate cause them to start "cogging", which can result in reduced pump longevity. One solution to this would be to simply install a 12 VDC power to the fuel pump, switched to "on" when the key is in the on or start position, then add a mechanical fuel pressure regulator. This disables the cability of the ECU to control the fuel pressure (which is considered by most to be a positive feature.)
Assuming that the installation of a switched 12 VDC power supply to the fuel pump was done correctly (and ignoring the obvious safety considerations of failing to do that,) there are yet other issues to consider. The 98+ Mustang's fuel pump sits down in a resevoir that holds the fuel around the pickup during cornering. That is not unusual. However, the resevoir for the 98+ Mustang is shorter, vertically, than that of the 96-97 Cobra, so the fuel pump does not fit into that resevoir as well. If you overcome that issue, then there is the fact that the Walbro fuel pump can quickly out-flow the jets that allow fuel to flow into the resevoir. This means that, at a high-fuel useage situation in a heavily modified Mustang, starvation could occur, particularly at lower fuel levels when passive filling (fuel running over the sides of and into the resevoir) is not available. One solution that has been developed to this problem is to drill holes in the resevoir to allow additional fuel to flow into the resevoir. However, this is not an all-positive solution, as this also allows fuel to run out of the resevoir, effectively limiting the fuel baffling purpose for which it was designed.
The right answer? Unfortunately, until Walbro released their 255 LPH High Performance Walbro fuel pump that fits properly into this application (mentioned at the top of this article) there wasn't one. The Walbro OE-replacement TCA903 turbine-style pump provides roughly 180 liters per hour of fuel at the standandard 45 psi / 12 vdc that the unit sees in an unmodified Mustang. 180lph is conservatively capable of fueling 470 naturally-aspirated horsepower--380 if the horsepower is turbo- or supercharger produced. Now, if you're sure that you need more fuel then the new 255 LPH 98-04 Mustang Fuel Pump can provide, then we have another alternative for you. We highly recommend the Fore Precision Fuel Hat, which allows you to install two PWM-style fuel pumps side-by-side in the fuel tank. Alternatively, for such a high-performance requirement, consider having an aftermarket fuel cell installed in the car. This will allow you to use something like the Walbro 255 LPH inline fuel pump that is available from Fuel-Pumps.Net, along with a mechanical fuel pressure regulator.
Yeah, the only difference between 97 and 98 is the whole evap valve setup. 98 has one hose and 97 has two.
DLF
Dedicated LVC Member
I guess you missed the link to all of that in post #33 of the thread I linked.
97MarkJA
Dedicated LVC Member
I do now, where it says HERE. I was distracted by KK's comment about a "magical fuel moving device"
Great info BTW, explains a lot.
Great info BTW, explains a lot.
97MarkJA
Dedicated LVC Member
If I stick with a motorcraft part it looks like two popular choices.
PFB81 which is the Ford GT pump. And
PFS204 which is the SVT focus pump.
Any thoughts?
The GT pump is actually cheaper by about $20 or so. It will require wiring changes at the pump but I will probably upgrade the wiring anyway.14 gauge wire just doesn't right, my GTO had 8 gauge running to each pump.
PFB81 which is the Ford GT pump. And
PFS204 which is the SVT focus pump.
Any thoughts?
The GT pump is actually cheaper by about $20 or so. It will require wiring changes at the pump but I will probably upgrade the wiring anyway.14 gauge wire just doesn't right, my GTO had 8 gauge running to each pump.