First 5.0 Endeavor

Discussion in '1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-' started by Illuminator, Mar 10, 2013.


  1. Illuminator

    Illuminator Active Member

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    I've had my 5.0 for around 5 years, most of those non-op as car came with more then a few (unknown at the time) issues when I bought it. There is tons of info on this site I've found and I'm sure there is yet a lot I have missed. Figured I would start a new thread to avoid changing topic in other's threads, even though most of my questions are related to what the poster is working on. This is my 1st foray into EFI cars, I'm an old school carb guy trying to learn the ropes, so bear with me. My car was fairly stout(for n/a) when I got it but not very street friendly as it had been previously dragged, and basically stripped of most items needed for driveability, comfort, etc; some good some far from. My plan is to start rehab, and hopefully get a few pointers from everyone here that know a ton more about these cars than I do. Honestly I never use to like the fox bodied cars that much and bought mine because a) it was fast b) had extra funds in hand. After discovering many needed fixes and getting an idea of what's possible i.e. affordable (w/o winning lotto) I decided the car had grown on me and was fun to drive. It has some essential mods (suspension, subframe, etc.) and quite a few that were well intended but need further improvement or replacement(rear disks, wiring, etc.). I'm hoping to throw some ideas out there and see what kind of input everyone offers along the way to help decide which way to go. As soon as Uncle Sam releases my "over" payment things should start moving along.
     
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  2. Illuminator

    Illuminator Active Member

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    OK...going to start with the bad... get that out of the way. The PO did a harness swap (possibly 4 banger to 8?) and to say the least....must have been on drugs. Most connectors mashed up, and splicing a 3 yr old could do better. Not to mention after pulling loom covers off I discovered many connections were wrapped in either duct tape or brown paper tape :bang: This is around the same time I started having starting and stalling issues. Being new to these cars I did a ton of research and took the checklist's I found (possibly jrichker, or hissen50?)had posted that were fairly in-depth and I was a bit overwhelmed, but followed them to the "T" w/o finding the problem. It could have been my ignorance because I still didn't know what all the sensors etc. did at that time. Main problem being fuel pump dropping off at idle after start. Traced all the wiring front to back and replaced the computer(didn't need too) and most of the fuel delivery electrics & egr(tps, iac, etc) Checked the relays(fp under seat, inertia sw.) and did a noid test, everything seemed ok. Still to this day haven't traced the problem down. Here is how I keep car running...
    [​IMG]

    Yeah I know....the wiring is still all exposed because I never solved the problem. Figured why go to all that trouble, and repeat it. I stumbled on a few fixes regarding stalling at the grounds around starter solenoid. I believe one of those is part of fuel circuit if I'm not mistaken. After seeing Mike686's post about the RJM harness I think I will get one of those and see if my problem goes away....I have repaired all the bad connections I could locate but that is a far cry from ideal as there are so many splices...and I am anal about perfect wiring! To make matters worse, I never knew there were so many damn wires in fuel injected cars...LOL Kinda miss the simple carb setup and half a dozen engine bay connections.
     
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  3. Illuminator

    Illuminator Active Member

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    Shot of top of motor with all wiring exposed and splicing
    [​IMG]
     
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  4. Illuminator

    Illuminator Active Member

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    Here is some more shots of engine compartment. More spliced wires, and latest trial of trying to keep belt from tossing as after deleting the a/c I used a ill recommended kit for ps mount which obviously wasn't ideal (bad routing of belt, rev idler mount and belt slipping off) In the meantime I tried my own fix short of going with the Ford Racing a/c delete that mounts the ps higher and uses stock idler location, or the threaded arm a lot use here I've seen. Only issue with my setup so far is there is a slight misalignment from new pulley, which I can machine the face on and get alignment squared up easilly. Seems to hold up at high r's vs. old setup.
    [​IMG]

    [​IMG]

    [​IMG]

    and just recently did a hood fly-up after forgetting pins DOH!! Think that will pull out?
    [​IMG]
     
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  5. FordRacing302

    FordRacing302 Active Member

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    I actually have the same question. I've been riding around with a smashed cowl for about 6 months...It had already been smashed and repaired once by the previous owner, So I think mine's beyond saving.
     
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  6. Illuminator

    Illuminator Active Member

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    Mine is so bad the wipers get stuck.....I never have forgot those pins before either... it must be the getting old thing. :scratch: Your car looks really clean... mine use to look decent before the PO's cheap paint job went away with the sun and winds here. Here's a year or so ago..
    [​IMG]

    I've also managed to bottom out the front valance and smash the fog lights in the meantime...Ugh!
     
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  7. mikestang63

    mikestang63 Mustang Master

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    First welcome to the site. Couple of observations and suggestions.

    1. First thing I would do is run for codes. You will probably get a ton, but you need to know what you are up against and a starting point. Here is a great tutorial.

    http://sbftech.com/index.php/topic,2471.0.html

    Jrichter also has a good writeup on this site. Don't be surprised if you can't run the tests because the wiring is all fubared.

    2. If I were you. I would go to a local junkyard and pull the factory wire loom from a similar year mustang and start fresh. It looks like you have a rats nest of slices, wrong gauge wires, and who knows what is grounded properly or what goes to what. You'll need to remove the dash, kick panels, and such. Start at the headlights and work your way back. It looks like the PO removed the "salt and pepper" shaped 10 pin connectors and spliced the wires together. IMO I would grab that harness off a donor 5.0 along with the factory wire looms and take the matching computer if it is there so everything is a matching. What you have now is not only not very functional, it is unsafe as that is a fire waiting to happen. You need to find out what that red wire spliced into the OBD for the fuel pump is going to. While you are at it, you can also hide most of the wiring inside the inner fenders to clean up the engine bay.

    Here is a great website that has all the schematics

    http://www.veryuseful.com/mustang/

    2. Is that a frikking pulley nose cover being used as a valve cover oil feed cap?
    3. Your idler pulley is too wide and the belt is going to wander back and forth. It looks like it is made for a 8 rib wide belt.
    4. If you are careful, you can slide hammer and dolly the cowl back to straight, but that is pretty bent up and there is not a lot of room. If you want it to look good as new best bet may be to cut that cowl section out, and either straighten it out off the car or find a replacement from a junkard, and then weld/ bondo/sand/paint it back in. Remember the cover piece is going back over it so that will hide some of the imperfections as long as the bolt holes line up.

    Good luck and please keep us posted.
     
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  8. MikeH686

    MikeH686 Mine is only two inches though.

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    Go with the rjm harness its the cleanest harness for you if you have gotten rid of egr
     
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  9. Illuminator

    Illuminator Active Member

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    Thanks for the welcome! I did pull the codes a few times, but that was a few years ago, and I can't recall the exact numbers but there were only 2-3 at most. All fuel related, and as far as I remember traced to relay issue.

    And as I mentioned the wires were in pretty bad shape when I took off the split looms and gobs of tape. Hence there are quite a few splices and most have at minimum the guage of wire that was original or better. I noted I have another harness but would prefer a brand new one or better then stock pending completeness. The salt and pepper shakers are actually intact and in decent condition, possibly the one area of the harness that survived getting hacked. They are just obscured in the pix. As a side note the interior is pretty much gutted except for seats and carpet and whatever necessary to drive the car. I need to get all new door panels, locate a good console, all new interior pieces as all of mine I had removed and a considerable stockpile of replacement parts I had purchased were stored at a close friends house who passed away last year and went into probate along with his house. That red wire to fuel pump is a jumper that keeps the signal to fuel pump operational when there is an issue keeping the system running. I believe it's in one of the write ups on here or perhaps elsewhere. I take credit for rigging that just so the car will stay running! Otherwise it starts and runs for a little while then dies. And in case you wondered, I replaced the in-tank pump with a 250lph unit and still had issues running lean, so added an in-line 250lph as well along the subframe rail around the passenger area which doesn't run off the computer signal, but as you know it won't keep the car running alone that far downstream.

    LOL I just barely caught on to that(nose cover oil cap) after getting the new idler pully and looking at it. Yes it is! Hey I did mentioned the PO did a few sketchy things to this car. And if you could see the fuel pressure guage up close it is actually an oil pressure unit. BTW the new idler pully "IS" a 6-rib but just a little wider then typical and does track the belt correctly. Hard to believe I made it all the way around the block and was headed back to my street when I finally hit 3rd and the hood launched. Can't believe I didn't break the windshield, and remember a neighbor lady pulling in her driveway that witnessed and was giggling. If I get to it I will try pulling the codes again, maybe start the whole test procedure fresh once more, but honestly I do believe I went though the whole procedure to the "T" at least twice a few years back. I tend to agree with MikeH686 that the RJM unit is the way to go.

    And this is only the beginning of all the "crap" I have been contending with on this car. Another work of art is the shady rear disk brake setup. PO had some right, a lot wrong! Mainly the axles were the wrong length and chewing bearings with every 5+ mile jaunt on the freeway. At 1st replacement I never noticed that they were not fully seated (long story, but my mother had just passed away and I was working on car to tune it out) Anyhow a month later they are blown out again. This time I realize the issue and also note the whole mounting of calipers is fishy at best. After researching quite a bit I figure he did the T-bird or svo swap if I recall correctly? Not certain, but the calipers have Varga or something to that effect on them, had a **** getting the right pads as I had no idea what they were. Rotors look like 4-lug with added holes. Anyhow I got the northracecar plates and had axles made locally (Alloy) to fix the issue. Still I don't care for the rear brakes that much, and hope to replace with something better, finances permitting. Also there's no e-brake because I am not certain which cables to use. If possible I would like to get bigger rotors, and more stout calipers for the rear, but I don't know if that is possible with the setup I currently have, short of going with the high dollar stuff.
     
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  10. Illuminator

    Illuminator Active Member

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    If the economy wasn't sucking as it stands, wouldn't it be nice to throw one of those 750hp+ shelby super snake motors in just for fun.... minus the 20k+(er make that 40k+) pricetag. Plus the warranty!
    [​IMG]
     
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  11. Illuminator

    Illuminator Active Member

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    Another question if anyone has pointers.....what usually is suspect if the car seems to lean out(cut out) at high rpm's but not consistantly? I mean sometimes it wraps up well, other times I get a sputtering effect. Think I mentioned above there's 2 fuel pumps in car ea at 250lph(tank/inline). Could this be fuel line constriction as they are only the factory lines and from what I can tell there are more then just a few areas where the lines seems to be looped a little tightly instead of least resistant path? What does everyone typically run if replacing the stock lines? Short of running a top-fuel setup that is... Appreciate the input from the many experts here. Also down the road a forced induction setup may be on the table.
     
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  12. jrichker

    jrichker StangNet's favorite TOOL SN Certified Technician Founding Member

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    The TFI module mounted on the distributor is usually the culprit for a high speed miss on a warm engine. If the problem does not occur when the engine is cold, the TFI module is definitely suspect. You may need a special socket to remove the TFI module, but most auto parts stores will have one for $5-$7.

    Be sure to use plenty of the heat sink grease on the new TFI and clean the old grease off the distributor.

    [​IMG]

    See Automotive Tools Specialty | Auto Mechanic & Technician Diagnostic, Testing Equipment | Thexton
    [​IMG]

    diagram courtesy of Tmoss & Stang&2Birds
    [​IMG]


    Fuel Pump Troubleshooting for 87-90 Mustangs

    Revised 10-Aug-2012 to update fuel pump run time on initial startup

    Clue – listen for the fuel pump to prime when you first turn the ignition switch on. It should run for 1-3 seconds and shut off. To trick the fuel pump into running, find the ECC test connector and jump the connector in the upper LH corner to ground.

    [​IMG]

    [​IMG]

    [​IMG]

    If the fuse links are OK, you will have power to the pump. Check fuel pressure – remove the cap from the Schrader valve behind the alternator and depress the core. Fuel should squirt out, catch it in a rag. A tire pressure gauge can also be used if you have one - look for 37-40 PSI. Beware of fire hazard when you do this.

    No fuel pressure, possible failed items in order of their probability:
    A.) Tripped inertia switch – press reset button on the inertia switch. The hatch cars hide it under the plastic trim covering the driver's side taillight. Use the voltmeter or test light to make sure you have power to both sides of the switch

    B.) Fuel pump power relay – located under the driver’s seat in most Mustangs built before 92. It is located under the MAF on 92 and 93 cars. Be careful not to confuse it with the A/C WOT cutoff relay which is in the same area. See the diagram to help identify the fuel pump relay wiring colors. Be sure to closely check the condition of the relay, wiring & socket for corrosion and damage.
    C.) Clogged fuel filter
    D.) Failed fuel pump
    E.) Blown fuse link in wiring harness.
    F.) Fuel pressure regulator failed. Remove vacuum line from regulator and inspect
    for fuel escaping while pump is running.

    The electrical circuit for the fuel pump has two paths, a control path and a power
    path.

    The control path consists of the inertia switch, the computer, and the fuel pump relay coil. It turns the fuel pump relay on or off under computer control. The switched power (red wire) from the ECC relay goes to the inertia switch (red/black wire) then from the inertia switch to the relay coil and then from the relay coil to the computer (tan/ Lt green wire). The computer provides the ground path to complete the circuit. This ground causes the relay coil to energize and close the contacts for the power path. Keep in mind that you can have voltage to all the right places, but the computer must provide a ground. If there is no ground, the relay will not close the power contacts.

    The power path picks up from a fuse link near the starter relay. Fuse links are like fuses, except they are pieces of wire and are made right into the wiring harness. The feed wire from the fuse link (orange/ light blue wire) goes to the fuel pump relay contacts. When the contacts close because the relay energizes, the power flows through the contacts to the fuel pump (light pink/black wire). Notice that pin 19 on the computer is the monitor to make sure the pump has power. The fuel pump has a black wire that supplies the ground to complete the circuit.

    Remember that the computer does not source any power to actuators, relays or injectors, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.

    [​IMG]

    Now that you have the theory of how it works, it’s time to go digging.

    All voltage reading are made with one voltmeter lead connected to the metal car body unless otherwise specified

    Check for 12 volts at the red wire on the inertia switch. No 12 volts at the inertia switch, the ignition switch is turned off or faulty or there is no power to the ECC (computer ) power relay. To be sure look for good 12 volts on the red wire on any fuel injector:
    good 12 volts mean the ECC relay is working. No 12 volts and the ECC wiring is at fault.
    Look for 12 volts on the red/green wire on the ignition coil: no 12 volts and the ignition switch is faulty, or the fuse link in the ignition power wire has blown. No 12 volts here and the ECC relay won’t close and provide power to the inertia switch. Check the Red/black wire on the inertia switch, it should have 12 volts. No 12 volts there, either the inertia switch is open or has no power to it. Check both sides of the inertia switch: there should be power on the Red wire and Red/Black wire. Power on the Red wire and not on the Red/Black wire means the inertia switch is open. Push the button on the side of it to reset it, and then recheck. Good 12 volts on one side and not on the other means the inertia switch has failed.

    Look for 12 volts at the Orange/Lt. Blue wire (power source for fuel pump relay). No voltage or low voltage, bad fuse link, bad wiring, bad ignition switch or ignition switch wiring or connections. There is a mystery connector somewhere under the driver’s side kick panel, between the fuel pump relay and the fuse link.

    Turn on the key and jumper the fuel pump test connector to ground as previously described. Look for 12 volts at the Light Pink/Black wire (relay controlled power for the fuel pump). No voltage there means that the relay has failed, or there is a broken wire in the relay control circuit.

    Pump wiring: Anytime the ignition switch is in the Run position and the test point is jumpered to ground, there should be at least 12 volts present on the black/pink wire. With power off, check the pump ground: you should see less than 1 ohm between the black wire and chassis ground.

    [​IMG]

    The yellow wire is the fuel tank sender to the fuel quantity gage. The two black wires are grounds. One ground is for the fuel tank sender and the other is the fuel pump. The ground for the fuel pump may be larger gauge wire that the fuel tank sender ground wire.

    Make sure that the power is off the circuit before making any resistance checks. If the circuit is powered up, your resistance measurements will be inaccurate.

    You should see less than 1 Ohm between the black wire(s) and ground. To get some idea of what a good reading is, short the two meter leads together and observe the reading. It should only be slightly higher when you measure the black wire to ground resistance.

    The Tan/Lt Green wire provides a ground path for the relay power. With the test connector jumpered to ground, there should be less than .75 volts. Use a test lamp with one side connected to battery power and the other side to the Tan/Lt Green wire. The test light should glow brightly. No glow and you have a broken wire or bad connection between the test connector and the relay. To test the wiring from the computer, remove the passenger side kick panel and disconnect the computer connector. It has a 10 MM bolt that holds it in place. With the test lamp connected to power, jumper pin 22 to ground and the test lamp should glow. No glow and the wiring between the computer and the fuel pump relay is bad.

    Computer: If you got this far and everything else checked out good, the computer is suspect. Remove the test jumper from the ECC test connector located under the hood. Probe computer pin 22 with a safety pin and ground it to chassis. Make sure the computer and everything else is connected. Turn the ignition switch to the Run position and observe the fuel pressure. The pump should run at full pressure.
    If it doesn't, the wiring between pin 22 on the computer and the fuel pump relay is bad.
    If it does run at full pressure, the computer may have failed.

    Keep in mind that the computer only runs the fuel pump for about 2-3 seconds when you turn the key to the Run position. This can sometimes fool you into thinking the computer has died. Connect one lead of the test light to power and the other lead to computer pin 22 with a safety pin. With the ignition switch Off, jumper the computer into self test mode like you are going to dump the codes. Turn the ignition switch to the Run position. The light will flicker when the computer does the self test routine. A flickering light is a good computer. No flickering light is a bad computer.
    Remove the test jumper from the ECC test connector located under the hood.

    Fuel pump runs continuously: The fuel pump relay contacts are stuck together or the Tan/Lt Green wire has shorted to ground. In extreme ghetto cases, the pump relay may have been bypassed. Remove the fuel pump relay from its socket. Then disconnect the computer and use an ohmmeter to check out the resistance between the Tan/Lt Green wire and ground. You should see more than 10 K Ohms (10,000 ohms) or an infinite open circuit. Be sure that the test connector isn’t jumpered to ground.
    If the wiring checks out good, then the computer is the likely culprit.

    Prior to replacing the computer, check the computer power ground. The computer has its own dedicated power ground that comes off the ground pigtail on the battery ground wire. Due to it's proximity to the battery, it may become corroded by acid fumes from the battery. It is a black cylinder about 2 1/2" long by 1" diameter with a black/lt green wire. You'll find it up next to the starter solenoid where the wire goes into the wiring harness

    If all of the checks have worked OK to this point, then the computer is bad. The computers are very reliable and not prone to failure unless there has been significant electrical trauma to the car. Things like lightning strikes and putting the battery in backwards or connecting jumper cables backwards are about the only thing that kills the computer.

    See the following website for some help from Tmoss (diagram designer) &
    Stang&2Birds (website host)

    http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

    http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

    http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif
     
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  13. Illuminator

    Illuminator Active Member

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    I believe I have replaced the TFI awhile back when trying one of my various attempts to rememdy the situation....may even have been from one of your posts, as I recall the thoroughness of the checklist.. :nice:

    Tried this test just now and my only problem is I have an in-line fuel pump as well as the in-tank unit, and in-line is far more noisy and masks any noise the in-tank unit may be making, I will need to disconnect in-line unit to make sure. I am getting pressure (40/41 psi) to guage at rail with normal operation. In-line unit "is not" ran off of computer circuit. I have read somewhere that it's possible to tap in (relay perhaps?) for a 2nd pump that will be controlled by computer, but wasn't sure of the safety in doing so or which lead to tap into. As your diagram shows, I have to ground the fuel pump test lead to keep car running after start and to be able to drive anywhere. I wired the test lead to chassis ground, I see in pic above that it goes back to test connector (ground black/white wire) Not sure if it makes any difference? I'm most certain that w/o the test lead jumpered the tank pump is non-op, altho I did do test above w/o jumper in place......had my daughter flip the key (minus FP test jumper) while under the car near tank and once again all I can hear is the in-line unit(quite noisey!). Before I go any further in the tests I think I need to determine the status of the tank pump...do you agree?
     
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  14. jrichker

    jrichker StangNet's favorite TOOL SN Certified Technician Founding Member

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    Unless you are running pressurized induction, the external fuel pump isn't necessary or useful. My advise is to concentrate on the in tank pump and get it working correctly.

    Copied from the FORD RACING PERFORMANCE PARTS catalog:

    PROPERLY SIZING FUEL SYSTEM COMPONENTS


    Fuel Pumps
    The following information is presented assuming the above information has been taken into consideration regarding BSFC, fuel pressure and specific gravity of the fuel being used. Most fuel pumps for electronic fuel injection are rated for flow at 12 volts @ 40 PSI. Most vehicle charging systems operate anywhere from 13.2v to 14.4v. The more voltage you feed a pump, the faster it spins which, obviously, will put out more fuel. Rating a fuel pump at 12 volts then, should offer a fairly conservative fuel flow rating allowing you to safely determine the pump’s ability to supply an adequate amount of fuel for a particular application.

    As previously mentioned, engines actually require a certain WEIGHT of fuel, NOT a certain VOLUME of fuel per horsepower. This can offer a bit of confusion since most fuel pumps are rated by volume, and not by weight. To determine the proper fuel pump required, a few mathematical conversions will need to be performed using the following information. There are 3.785 liters in 1 US Gallon. 1 gallon of gasoline (.72 specific gravity @ 65° F) weighs 6.009 LBS.

    To be certain that the fuel pump is not run to its very limit, which could potentially be dangerous to the engine, multiply the final output of the fuel pump by 0.9 to determine the capacity of the fuel pump at 90% output. This should offer plenty of ‘cushion’ as to the overall “horsepower capacity” of the fuel pump.

    To determine the overall capacity of a fuel pump rated in liters, use the additional following conversions:
    (Liters per Hour) / 3.785 = Gallons
    Multiply by 6.009 = LBS/HR
    Multiply by 0.9 = Capacity at 90%
    Divide by BSFC = Horsepower Capacity
    So for a 110 LPH fuel pump:
    110 / 3.785 = 29.06 Gallons
    29.06 x 6.009 = 174.62 LBS/HR
    174.62 x 0.9 = 157 LBS/HR @ 90% Capacity
    157 / 0.5 = 314 HP safe naturally aspirated “Horsepower Capacity”

    Safe “Horsepower Capacity” @ 40 PSI with 12 Volts
    60 Liter Pump = 95 LB/HR X .9 = 86 LB/HR, Safe for 170 naturally aspirated Horsepower
    88 Liter Pump = 140 LB/HR X .9 = 126 LB/HR, Safe for 250 naturally aspirated Horsepower
    110 Liter Pump = 175 LB/HR X .9 = 157 LB/HR, Safe for 315 naturally aspirated Horsepower
    155 Liter Pump = 246 LB/HR X .9 = 221 LB/HR, Safe for 440 naturally aspirated Horsepower
    190 Liter Pump = 302 LB/HR X .9 = 271 LB/HR, Safe for 540 naturally aspirated Horsepower
    255 Liter Pump = 405 LB/HR X .9 = 364 LB/HR, Safe for 700 naturally aspirated Horsepower

    Note: For forced induction engines, the above power levels will be reduced because as the pressure required by the pump increases, the flow decreases. In order to do proper fuel pump sizing, a fuel pump map is required, which shows flow rate versus delivery pressure.

    That is, a 255 liter per hour pump at 40 PSI may only supply 200 liters per hour at 58 PSI (40 PSI plus 18 lbs of boost). Additionally, if you use a fuel line that is not large enough, this can result in decreased fuel volume due to the pressure drop across the fuel feed line: 255 LPH at the pump may only result in 225 LPH at the fuel rail.


    My Comments:

    A lot of people oversize the fuel pump by buying a 255LPH pump thinking that the fuel pump regulator will just pass the excess gas back to the tank. It does, but… Did you ever consider that circulating the fuel around as a 255 LPH pump does will cause the gas to pickup engine heat? What happens to hot gasoline? It boils off! With most of the 5.0 Mustangs having the carbon canister removed or disabled, the car stinks like gas, and the gas mileage drops since the hot fuel evaporates away into the air.
     
    #14
  15. Illuminator

    Illuminator Active Member

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    I believe a source of the issue may be very well the fuel lines. Say I am using 24lb injectors and hypothetically at their rated potential with cam, TB, MAF, etc....what would be the required pump size? or at this point is the stock lines just bottle necking the supply in general?

    Although extremely pricey, the Aeromotive Stealth system is really appealing, although the price is a bit stiff, includes everything from baffled Cobra style tank, new -an lines(can't recall size; 10??), fuel rails, regulator, pump, plumbing etc and available for different HP levels... I replaced in-tank pump once and thoroughly cleaned it out etc. Shortly after doing so (cpl months) I started having stall issues. I even considered someone had contaminated the tank with foreign debris because I had unknowingly parked in front of someones house a few times that had issues with that.....Good time to replace I guess.
     
    #15
  16. jrichker

    jrichker StangNet's favorite TOOL SN Certified Technician Founding Member

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    A 155 LPH will support 440 naturally aspirated HP. It is doubtful that you will need more than that with a 302/331/351/383 cu in engine

    Safe “Horsepower Capacity” @ 40 PSI with 12 Volts
    60 Liter Pump = 95 LB/HR X .9 = 86 LB/HR, Safe for 170 naturally aspirated Horsepower
    88 Liter Pump = 140 LB/HR X .9 = 126 LB/HR, Safe for 250 naturally aspirated Horsepower
    110 Liter Pump = 175 LB/HR X .9 = 157 LB/HR, Safe for 315 naturally aspirated Horsepower
    155 Liter Pump = 246 LB/HR X .9 = 221 LB/HR, Safe for 440 naturally aspirated Horsepower
    190 Liter Pump = 302 LB/HR X .9 = 271 LB/HR, Safe for 540 naturally aspirated Horsepower
    255 Liter Pump = 405 LB/HR X .9 = 364 LB/HR, Safe for 700 naturally aspirated Horsepower
     
    #16
    02 281 GT likes this.
  17. Illuminator

    Illuminator Active Member

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    Only got so far tonight as it was getting dark shortly after starting.... disconnected the power to the in-line pump and concluded the circuit isn't active w/0 the jumper grounded. With jumper grounded I can hear the pump running but no pressure to the rails (at least not enough to move the needle on guage at shr. valve) Tomorrow I will pull the seat out and try to locate my tester to proceed with the rest of the tests. Thanks for all the tech info jrichker!! Most invaluable! :word:
     
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  18. Illuminator

    Illuminator Active Member

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    Solved half the problem.....still have electrical issue though. After pulling tank and pump I discovered that when the pump was replaced the hose that goes from hard line to pump never had its clamp tightened, and hose was almost all the way off. Anyhow fixed that and re-installed tank. Car now runs on the in-tank pump and I can remove the inline unit. Still have to jumper the test connector to get pressure though. I got through most of the tests as per jrichker's post upto the part of checking ground resistance to fuel pump. Hopefully tomorrow can finally trace that down. While tank was out got a better view of the lack of clearance for wider tires and noticed a couple areas maybe someone could shed light on. Notice in the pix the jagged/torn/welded areas of metal next to the quad mounts....anyone know what that is/was? Is this even the original axle housing?
    [​IMG]
    [​IMG]


    [​IMG]

    And rearend with sun glare......yeah that's Mama's 2013 vert you can see the wheel from under the car....
    [​IMG]
     
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  19. Illuminator

    Illuminator Active Member

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    Ok I am at the part in diagnosis of the relay feeds. With no jumper grounded, there's power to the Orange/Lt. blue and with ignition on, hot to the Red/Blk. stripe side. The Pink/Blk. stripe don't become hot unless the jumper is attached. If I'm understanding correctly the tan/Lt. green wire is most likely the culprit (or eec/eec ground) and I need to verify that at this point. Just making sure I don't miss a step as I have gone through this procedure a few times and seem to keep missing something. So far have followed to the T with everything else ok except for the need for jumper as no pump firing on ignition on. Also had a hard time finding a good spot to do the ground to pump resistance test as touching almost any chassis area was not pulling any measurements or jumpy at best. Think I would need to power wash or sandblast under there to get a decent connection (it's fairly dirty)


    Thanks again
     
    #19
  20. 02 281 GT

    02 281 GT Active Member

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    I'm not sure about the jagged looking area, but one thing people do to gain a little bit of extra clearance for tires is flip the quad shocks. IE: mount the end which is currently mounted to the frame to the rear end and vice versa. I never did this personally, so I can't say if it affects wheel hop in any way. Perhaps someone who has can chime in.
     
    #20

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