car drops fuel presure at 5800rpm, need help - Ford Mustang Forums : Corral.net Mustang Forum
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post #1 of 45 Old 04-26-2011, 09:41 AM Thread Starter
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car drops fuel presure at 5800rpm, need help

i am running a Ford GT intake pump. when i am in higher rpm's my fuel pressure is at 40 psi. when i get to 5800 rpm the pressure drops to 30 psi. the car made 416 rwhp at 6k. it was dropping fuel pressure on the dyno. my tuner said this pump should be good for 500rwhp. is that right? should i run an inline pump to help this in take pump? or should i just swap out the GT pump. the car also will not build fuel pressure when i 1st hit the key to prime the fuel system. i've put a manual gauge on the pressure feed line at the fuel rail and the pressure spikes, but then falls right off. i assume the pump is leaking down. this pump maybe has 3k miles. thanks


1998 GT Rio Red
T-trim, Ported SVO heads, SVO intake, SHM cams, Teksid, Diamond pistons, Manely rods, Cobra crank, AIS meth kit, T-56, and GT 500 twin disc
507hp 416tq
Oct. 06 issue of 5.0 and super fords
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post #2 of 45 Old 04-26-2011, 11:34 AM
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Whats the rest of your fuel system ? Is it return or returnless

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post #3 of 45 Old 04-26-2011, 12:08 PM Thread Starter
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96-97 fuel rails with stock fuel pressure reg, 60lbs injectors, return style system and i swapped to the 94-97 style tank. I got rid of the fuel delivery module setup

1998 GT Rio Red
T-trim, Ported SVO heads, SVO intake, SHM cams, Teksid, Diamond pistons, Manely rods, Cobra crank, AIS meth kit, T-56, and GT 500 twin disc
507hp 416tq
Oct. 06 issue of 5.0 and super fords
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post #4 of 45 Old 04-26-2011, 12:22 PM
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What kind of boost are you running??? If your running stock fuel rails your likely pulling too much fuel out of the rails with the 60lb injectors. I had the same problem on my 96 cobra when i switched from 42's to 60's.
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post #5 of 45 Old 04-26-2011, 12:38 PM Thread Starter
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I dont run a boost gauge, but i think on the dyno we were seeing 10 psi at 6k. The car should spin to 7k rpm. I am running a 3.33 pulley and a stock lower. Hhhmmm, i could see big injectors doing that. Any other ideas to try?

1998 GT Rio Red
T-trim, Ported SVO heads, SVO intake, SHM cams, Teksid, Diamond pistons, Manely rods, Cobra crank, AIS meth kit, T-56, and GT 500 twin disc
507hp 416tq
Oct. 06 issue of 5.0 and super fords
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post #6 of 45 Old 04-26-2011, 01:05 PM
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I find it hard to believe that the rails would be getting drained from the 60's...There are a lot of fox body guys running 60's with factory rails making around 500 rwhp.

I'm thinking it is either pump or regulator related.

Dustin,

Have you tried priming the pump a few times to see if it will hold pressure? Maybe the check ball is failing at the pump?

'91 GT: SOLD

'04 GT: Forged bottom end, MHS Stg 3 PI heads, Hi-Tech Custom Cams, MHS Vic Jr + elbow, custom turbo kit, Precision 7175, T-56 & 3.27's. 785rwhp/725rwtq @ 20 psi.
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post #7 of 45 Old 04-26-2011, 01:27 PM Thread Starter
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Yeah, when i hooked the mech gauge to the presure line at the fuel rail i cycled the key a few times. No go. I deffinetly think the check ball is f'ed. I also hooked the mechanical gauge to the return side of the fuel rail and i saw no presure spikes when cycling the key. I was really leaning twards a stuck open regulator like we talked about the other night. I am thinking the pump is faulty, which is crazy cause its been doing this since day one. I think the pump has like 3k miles on it

1998 GT Rio Red
T-trim, Ported SVO heads, SVO intake, SHM cams, Teksid, Diamond pistons, Manely rods, Cobra crank, AIS meth kit, T-56, and GT 500 twin disc
507hp 416tq
Oct. 06 issue of 5.0 and super fords
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post #8 of 45 Old 04-26-2011, 01:38 PM
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I had a smiliar problem on my 89. It turned out to be my fuel pressure regulator. It wasnt holding pressure consistently and when it did it would bleed back after a few minutes
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post #9 of 45 Old 04-26-2011, 01:41 PM
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Quote:
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Yeah, when i hooked the mech gauge to the presure line at the fuel rail i cycled the key a few times. No go. I deffinetly think the check ball is f'ed. I also hooked the mechanical gauge to the return side of the fuel rail and i saw no presure spikes when cycling the key. I was really leaning twards a stuck open regulator like we talked about the other night. I am thinking the pump is faulty, which is crazy cause its been doing this since day one. I think the pump has like 3k miles on it
Can you get your hands on a stock pump or another GT pump to test, to see if it holds pressure?

'91 GT: SOLD

'04 GT: Forged bottom end, MHS Stg 3 PI heads, Hi-Tech Custom Cams, MHS Vic Jr + elbow, custom turbo kit, Precision 7175, T-56 & 3.27's. 785rwhp/725rwtq @ 20 psi.
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post #10 of 45 Old 04-26-2011, 03:51 PM
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[QUOTE=Macs Stang;10484252]I find it hard to believe that the rails would be getting drained from the 60's...There are a lot of fox body guys running 60's with factory rails making around 500 rwhp.

I am talking about factory 96-98 cobra fuel rails. I was running 15psi with the stock fuel rails using the 60's with an Aeromotive fpr and experienced the same problem. Exactly what fuel rails are you running??? The fuel pump could very well be the problem too. You need to get a boost gauge hooked up!!!!!

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post #11 of 45 Old 04-26-2011, 07:58 PM
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Put a fuel gauge on the regulator and see if it holds pressure, if it doesnt its probably the regulator. Like i said earlier my 89gt had that problem last year.
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post #12 of 45 Old 04-26-2011, 09:30 PM Thread Starter
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I hooked a pressure gauge up after the regulator and cycled the key and i did not have pressure. The funny thing is, i pulled the fuel pump assy out and stuck it in a can of gas and cycled the key. Fuel came out the return side of the sender. Not alot, but some did. But if the regulator was sticking open, i would have gotten a pressure reading on my gauge

1998 GT Rio Red
T-trim, Ported SVO heads, SVO intake, SHM cams, Teksid, Diamond pistons, Manely rods, Cobra crank, AIS meth kit, T-56, and GT 500 twin disc
507hp 416tq
Oct. 06 issue of 5.0 and super fords
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post #13 of 45 Old 04-26-2011, 10:14 PM
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If the gauge is after the regulator you shouldn't see pressure as there is nothing restricting it. Put the gauge right before the regulator and see what it does. I still vote for the pump or regulator causing the issue.

'91 GT: SOLD

'04 GT: Forged bottom end, MHS Stg 3 PI heads, Hi-Tech Custom Cams, MHS Vic Jr + elbow, custom turbo kit, Precision 7175, T-56 & 3.27's. 785rwhp/725rwtq @ 20 psi.
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post #14 of 45 Old 04-27-2011, 09:42 AM
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Macs Stang is right, mount the gauge before the regulator when trying to check the pump pressure. Your still not clear what fuel rails your using...... I can't remember how the factory stuff is arranged, but is the factory FPR a 1:1 ratio or ???? They are non adjustable correct??? I had an Aeromotive FPR on my factory rails and had to set the pressure @ 50psi with the vacuum source unhooked. It was a 1:1 ratio and gave me 60psi fuel rail pressure when i was set-up running 10lbs boost. I think your starting with the pressure too low...... Still believe your draining the rails at the pressure your running. I assume your not running an FMU either???
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post #15 of 45 Old 04-28-2011, 09:40 AM
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We tested a few things last night...when priming the pump the fuel pressure gauge read zero, even after cycling the pump three times. My vote still stands as a bad regulator. The pump holds pressure when the engine is running.

'91 GT: SOLD

'04 GT: Forged bottom end, MHS Stg 3 PI heads, Hi-Tech Custom Cams, MHS Vic Jr + elbow, custom turbo kit, Precision 7175, T-56 & 3.27's. 785rwhp/725rwtq @ 20 psi.
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post #16 of 45 Old 04-28-2011, 01:29 PM
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Cool, hope you guys get it sorted out soon!
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post #17 of 45 Old 05-12-2011, 08:23 AM
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I am having a similar problem at the dyno with my procharged 4v setup on my 98. When it reaches 4700rpm and 480hp it starts dropping pressure. I am running a Fore dual pump setup. Looks like I am running on 1 pump and I can not tell as the previous shop wired both pumps to 1 circuit. I have asked them to wire each pump independent as it will make it easier to diagnose in the future.

As for your issue have you checked the voltage at the pump when it starts dropping? Maybe the CCRM is not providing enough voltage or you alternator is having an issue and not providing enough voltage at that rpm.
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post #18 of 45 Old 05-12-2011, 09:13 AM Thread Starter
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Thats where i am at with it right now. I am gonna run a 12 ga wire back from the battery to a relay in my trunk. If that doesnt work, i am gonna replace the pump

1998 GT Rio Red
T-trim, Ported SVO heads, SVO intake, SHM cams, Teksid, Diamond pistons, Manely rods, Cobra crank, AIS meth kit, T-56, and GT 500 twin disc
507hp 416tq
Oct. 06 issue of 5.0 and super fords
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post #19 of 45 Old 05-12-2011, 09:07 PM
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Thats where i am at with it right now. I am gonna run a 12 ga wire back from the battery to a relay in my trunk. If that doesnt work, i am gonna replace the pump
Muuuuuuuuuuuuuustang! Let me know if you need help, neighbor.

'91 GT: SOLD

'04 GT: Forged bottom end, MHS Stg 3 PI heads, Hi-Tech Custom Cams, MHS Vic Jr + elbow, custom turbo kit, Precision 7175, T-56 & 3.27's. 785rwhp/725rwtq @ 20 psi.
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post #20 of 45 Old 05-13-2011, 10:50 PM
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It has been verified that one of my fuel pumps was not working. Going to replace both at the same time.
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post #21 of 45 Old 05-15-2011, 02:37 PM Thread Starter
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Well the other day i was driving home and my car was dropping fuel presure under normal accel and cruise. Looks like i have a bad pump also. The GT pumps sure went up in price!! Now i need to figure out what pump to run

1998 GT Rio Red
T-trim, Ported SVO heads, SVO intake, SHM cams, Teksid, Diamond pistons, Manely rods, Cobra crank, AIS meth kit, T-56, and GT 500 twin disc
507hp 416tq
Oct. 06 issue of 5.0 and super fords
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post #22 of 45 Old 05-15-2011, 09:19 PM
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Here is the write up about the 98s

Stangs of South Florida
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post #23 of 45 Old 05-16-2011, 01:08 PM
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Here is the write up about the 98s

Stangs of South Florida
You need to register to view that thread.

Also, it appears the pump may have not been the issue. Talking with him last night, he still was having issues after he swapped to his factory pump to rule out the GT pump...

'91 GT: SOLD

'04 GT: Forged bottom end, MHS Stg 3 PI heads, Hi-Tech Custom Cams, MHS Vic Jr + elbow, custom turbo kit, Precision 7175, T-56 & 3.27's. 785rwhp/725rwtq @ 20 psi.
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post #24 of 45 Old 05-16-2011, 09:40 PM
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I did a cut and paste

I just received an email from a member of the Corral asking about my fuel system. So, instead of answering his question via email, which makes using pictures as a reference difficult, I thought we could turn this into an interesting discussion here.

So let's get started.

First, we'll start with the test mule, my 98 Cobra.

Here's a picture of the car from when I first bought it in 2003. n fact, when I bought it, it had roughly 42000 miles on it, a BBK CAI, PRO-M mass air meter, Superior 31 spline axles, and a PowerTrax locking differential that destroyed itself in less than 3000 miles. I

The car now has 52000 miles on it, believe it or not.



Now, because the car is a 98, it's got some challenges that make a fuel system different for the 98 than both the 97 and older cars, as well as different than that of the 99+ cars.

In 1998 Ford went to the "basket in a tub" system which, at least on paper, was a good idea. The technology behind it was pretty sound: put the fuel pump in a "basket" that was fed fuel and "always" kept full.

The way it was designed to work, in a stock car, was pure genius. Suck fuel from a low point in the tank and make it so the fuel pump was always submerged in fuel, even if the tank was low.

The problems started showing up when people wen to bigger than stock fuel pumps and lines. Suddenly, the basket became a limitation, since now you had a fuel pump that was capable of emptying the basket MUCH faster than the stock lines in the tank could refill it.

As you can imagine, that's bad.

So, being the creative souls we are, people (including myself) started hacking up the fuel baskets. This was a band-aid fix that uncovered an issue that caused a LOT of trouble for Walbro.

What people didn't realize was the fuel system in the 98's are a "hybrid" system. What that means to you cats and dogs out there is it's got a variable voltage fuel pump like the soon to be released in 1999 RETURNLESS fuel system.

This increases and/or decreases the voltage to the pump, thereby controlling both fuel pressure and fuel flow in the tank.

It's a great idea, except for the fact that very few people realized this was going on. We all assumed it was the same as every other mustang out there, and when you put a fuel pump in the tank that wasn't designed to be run with variable voltage, like 99% of the Walbro line, it killed the pumps with surprising quickness.

Personally, I killed a pump in less than 50 miles in a full tank. (crazy, I know.)

So, this leaves you three possible fixes:

Switch to a 97 tank and direct wire the fuel pump
Find the right fuel pump (Aviator, Focus, etc...)
Run a sumped and baffled tank and external fuel pumps


For me, I took the high road and picked up a Home - Glenn's Performance sumped and baffled fuel tank and I’m running two external fuel pumps.(More on that later.)

One side benefit of this tank is it eliminates the need for a drop in style fuel pick up. You suck fuel directly out of the sump, which is always the lowest point in the tank.

This tank is designed with the driver in mind. I have been told you can run this tank to basically empty and not have fuel issues. While I don't recommend letting the fuel supply get that low in a boosted application, things happen. This design also means you don't have to worry as much about around town driving related fuel starvation like SOME tanks (older Aeromotive, for example) where the fuel can be as high as 1/4 of a tank remaining, but if you make a hard turn the fuel sloshes away from the pickup, causing a lean condition.

Now, the only real issue with that tank is that it's designed to be used with a 97 and older car. So, as you'll see in the photo below, the plug design is different from a 98 to a 97. This means you'll have to get our hands on the proper harness out of an older car and splice it into your 98+ harness to make the fuel level gauge work.

So, as you can see; this is a completely different setup. (It's an easy swap.)

One last thing: if you want to cause trouble for yourself in a modular powered SN95, go ahead and simply weld on a sump. They're cheap to buy and have welded on, but since there are no internal fuel controls (baffles, basically) inside the tank, you're going to have low fuel level starvation issues on not only hard turns, but I've seen it rear its ugly head even under hard braking and launch conditions. I've seen dozens, and they're hard to diagnose if you don't know what you're looking for.

So now you've got your fuel tank sorted out, what do we do about lines, rails, regulators, and the all important fuel pump?

Well, here's what I did, but please keep in mind that this is a fuel system for a twin 60mm turbo car with a built motor and ported heads. Your individual needs may vary, but this system will support upwards of 1000 RWHP.

Now, in addition to the tanks, you need to look at fuel pumps. For most people, it's pretty simple to go is with some sort of Ford pump. As I mentioned earlier, the Focus, Aviator, and Ford GT pumps have worked pretty well for quite a few people. The issue is once you climb past a certain point, even two of those pumps reach their limits.

I went straight to the top with this and I'm running two Bosch 984 fuel pumps. (they were SUPPOSED to be 044 pumps, which flow a little more, but my parts guy grabbed the wrong ones. No worries, as these should work just fine.)

Here's the part number:

Here's a link to Bosch fuel pump flow, sizes, and amperage requirements.

http://www.lucasinjection.com/_borders/fuelpumps.pdf .

So, in that document you'll see that the 984 flows 165 LPH (liters per hour), whereas the 044 is 200LPH. If I have any fuel issues at all, which I don't anticipate, I'll pick up the 044 pumps. They'll be a 3 minute swap given my current setup.

I digress.

Now, to give you an idea of how big these pumps are, here's a picture of my 984 pump next to the stock pump that came out of my Cobra.

Now, to really drive home the point, here's a picture that should put these pumps into prospective.

Yes. I'm running two of these pumps.

When it comes to wiring the actual pumps themselves, I recommend (and use personally) them being wired through individual 30 amp Relays from Painless. (Summitt sells them for 30 bucks.)

The reason you want to run them to individual relays is to decrease the likelihood of both pumps failing at once. By running them on a single relay and single power source you kill both pumps by tripping a single relay.

I'd like to have at least one pump to get me home, if possible.

Anyway, you can find them here:
404 File Not Found - SummitRacing.com

And here are installation instructions:

Painless Performance When it comes to filters, I recommend an Aeromotive 100 micron and 10 micron.

Remember: 10 micron filter AFTER the pump and the 100 micron filter BEFORE the pump, otherwise you will starve the pump for fuel.

Quote:
Originally Posted by Aeromotive
Noting the appropriate flow directions, install the provided fuel filter, Aeromotive p/n 12301, on the fuel pump outlet
and the other fuel filter, Aeromotive p/n 12304, on the fuel pump inlet.
p/n 12301 = 10 micron
p/n 12304 = 100 micron

1-8: http://www.aeromotiveinc.com/pdf/17141.pdf

So, once you have the pumps, lines, tank, and filters sorted out, here's what you end up with as a finished product:

Now that you've got your pumps and filters figured out, you need to focus on the lines. I've got stainless braided hoses with A/N (which stands for Army/Navy) fittings from front to back.

From the FPR I'm running a -6 "return" line that takes fuel BACK to the fuel tank.

While we're talking about fuel making a circuit from the tank all the way back to the tank, let's talk about temperature. I'm sure a bunch of you have heard that Aeromotive fuel pumps have been problematic. While this is typically true, most people don't know WHY they're problematic.

I'm going to be redundant here for a second, but here's the short answer: Aeromotive, and other big single pumps, flow all out, all the time. This never gives the fuel a chance to cool as it makes its trip from tank back to tank.

Additionally, some people confuse the pressure increase with the fuel boiling. They think because the fuel is flowing so quickly that it hits the regulator, gets backed up, and THAT causes the fuel temperature to to increase , but that's not the whole story.

Things to consider:

When it hits the regulator it's immediately dumped into the return line. What we're describing above would cause the fuel to "dead head" at the regulator and that would cause a whole other series of problems unrelated to temperature.
Increasing the pressure of liquid raises the boiling point.


Think of it this way; removing a hot radiator cap forces the coolant out violently because the system is pressurized, not because it's suddenly boiling. When you provide pressurized ANYTHING with a sudden escape point it's going to try to do so as quickly as it can. That's why you only have that initial spray of coolant upon removal of the cap. Once the pressure has been released the coolant goes back to business as usual.

Without any other contributing factors, fuel temperature typically stays 10-15 degrees above room temperature.

Some people suggest some fuel pumps (Aeromotive in particular) cause problems because they're "too efficient." It's not the pump being "too efficient", but more of the pump working harder than necessary. (Anyone can make a pump that'll flow high volumes of liquid.) It's heat related vapor lock caused by the high recirculation rate at cruise.

What really causes it is heat the fuel absorbs from the supporting fuel system hardware. (The rails are the big culprit.) Fuel absorbs heat from the rails and is returned to the tank, then almost immediately sucked back into the lines by the pump.

Since the fuel has little time to cool it eventually gets hot enough to boil in the inlet to the pump. The pump doesn't quit, it simply stops drawing liquid fuel. (I can't imagine the car runs well on foam/vapor.)

The vapor lock is caused by the high inlet vacuum generated by their roller vane pump. (as opposed to gerotor, sliding vane, etc...) Vacuum, by definition, lowers the pressure of the fuel on the inlet side. This lower pressure causes the fuel to flash sooner. (the opposite effect of what we discussed a second ago.)

When you shut off the car the fuel cools and stops boiling. (this is made worse when you have anything other than a full tank.)

A "returnless"s system typcally uses a variable voltage pump, which is the same thing as the new Aeromotive pump controller. Great idea, just like the "basket in a bucket" idea, but only if you can get either of them to work.

Anyway, now that we're done talking thermodynamic properties of liquids in a pressure elevated environment...

So, as I said before, this setup will support 1000+ RWHP with relative ease.

I think that's pretty much everything we need to talk about, but if I'm leaving anything out please let me know.

I hope this helps someone. I know it's an expensive and nerve-racking (is that spelled correctly?) decision-making process.

Later peeps,
Alan
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post #25 of 45 Old 05-17-2011, 12:32 AM Thread Starter
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cool post, thanks for posting it. the only problem i have with it, is if you look at the wiring diagram, i don't see how the PCM controls the amount of voltage to the pump. the PCM grounds the fuel pump relay and power flows right to the pump. i am still going to run a 12ga wire back to a relay and rewire the fuel pump. my tuner thinks i am not getting enough voltage to the pump at high rpm's. we will see.

1998 GT Rio Red
T-trim, Ported SVO heads, SVO intake, SHM cams, Teksid, Diamond pistons, Manely rods, Cobra crank, AIS meth kit, T-56, and GT 500 twin disc
507hp 416tq
Oct. 06 issue of 5.0 and super fords
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post #26 of 45 Old 05-17-2011, 03:00 PM
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Have you ruled out the FPR? This would have been first on my list since its about a million times easier to swap out than dropping the tank...and you have fuel but the pressure isn't consistant? hmmm what controls the consistancy of the fuel pressure.....hmmmm.
sorry for being so blunt but seriously, how can you even think this is anything other than the FPR?

Last edited by RCwhat; 05-17-2011 at 03:05 PM.
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post #27 of 45 Old 05-18-2011, 10:19 PM
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We dropped the tank the other night. The rubber line from the pump to the metal feed line had a small hole in it. Took the car for a drive yesterday and the fuel pressure kept rising with boost. Looks like we solved the issue, hopefully the pressure stays consistant.

'91 GT: SOLD

'04 GT: Forged bottom end, MHS Stg 3 PI heads, Hi-Tech Custom Cams, MHS Vic Jr + elbow, custom turbo kit, Precision 7175, T-56 & 3.27's. 785rwhp/725rwtq @ 20 psi.
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post #28 of 45 Old 05-21-2011, 11:20 PM
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We dropped the tank the other night. The rubber line from the pump to the metal feed line had a small hole in it. Took the car for a drive yesterday and the fuel pressure kept rising with boost. Looks like we solved the issue, hopefully the pressure stays consistant.
WOOOO WOOOO

91 Silver coupe KC B50 331 Tremec, AFR 185's Track Heat intake, Aeromotive fuel system, 50 pound injectors PMS Vortech t-trim yadeda And I wonder why I cant move out?
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post #29 of 45 Old 05-21-2011, 11:53 PM
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WOOOO WOOOO
Doin' it right son.

'91 GT: SOLD

'04 GT: Forged bottom end, MHS Stg 3 PI heads, Hi-Tech Custom Cams, MHS Vic Jr + elbow, custom turbo kit, Precision 7175, T-56 & 3.27's. 785rwhp/725rwtq @ 20 psi.
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post #30 of 45 Old 06-01-2011, 01:28 PM
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Looks like we might be seeing the ugly drop again. We are thinking that the pump might be losing voltage as the higher load is applied to the pump...would running a dedicated line from the battery to a relay and then to the pump solve the issue of voltage drop? Or would a BAP be the better alternative?

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post #31 of 45 Old 06-01-2011, 04:02 PM
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Have you ruled out the FPR? This would have been first on my list since its about a million times easier to swap out than dropping the tank...and you have fuel but the pressure isn't consistant? hmmm what controls the consistancy of the fuel pressure.....hmmmm.
sorry for being so blunt but seriously, how can you even think this is anything other than the FPR?
seems you missed this the first time around....
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post #32 of 45 Old 06-01-2011, 04:06 PM
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Looks like we might be seeing the ugly drop again. We are thinking that the pump might be losing voltage as the higher load is applied to the pump...would running a dedicated line from the battery to a relay and then to the pump solve the issue of voltage drop? Or would a BAP be the better alternative?
neither, your fuel pressure regulator is junk and acting up (they like to be all inconsistant like this when they #### the bed) just replace it already. And if your FPR was working properly the load on the pump should be fairly consistant as long as its not cavitating.
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post #33 of 45 Old 06-01-2011, 04:11 PM
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I had a smiliar problem on my 89. It turned out to be my fuel pressure regulator. It wasnt holding pressure consistently and when it did it would bleed back after a few minutes
exactly, seems this guy just really doesn't want his car fixed as multiple people told him how to solve it and instead he just ignores us and is just swapping parts without any educated reasoning behind it. I guess you can't help people who won't accept the help....
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post #34 of 45 Old 06-09-2011, 01:05 PM Thread Starter
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Fuel pressure is consistant until 5800 where it falls off. I swapped the regulator and it didn't fix it. any other ideas? we are gonna rewire the pump tonight

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post #35 of 45 Old 06-09-2011, 03:52 PM
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I am not 100% sure, but it just sounds like your pump can't keep up. If rewiring it doesn't fix it, I would definetly try a BAP. Good luck man!

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