You can't just "delete" your regulator. The removal of the external regulator is required when installing a non stock alternator with an internal regulator.
2F HOLLY SNIPER EFI (1 Viewer)
- Thread starter EndlessAloha
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- #42
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- #43
So you didn’t even have to run a return line at all? You just capped it off? Maybe that’s my problem. I ran a return line back in the OEM return line back to the side of the tank, where the original return spout was...
You must have a return. Yours is good. What Jdc1, myself and a few others have done is, not use the regulator in the Sniper, cap it off and install a remote regulator. Then a return line is run from the remote regulator back to the tank. In Jdc1’s pic, the return comes off the bottom of the regulator.
Your pump puts out way over 60 psi. The regulator holds back 60 psi and the excess gets released which must be plumbed back to the tank.
Usually the cycle is like this, Tank>pump>fuel injector/rail>regulator>tank. You CAN'T have a regulator BEFORE the fuel injectors because the return line is open to tank pressure (Patm + Pvapor) and you would have no (some but insufficient, use Bernoulli) liquid fuel pressure. This is all very simple stuff and should be available in the Holley manual. If you don't approach this systematically you will/and seem to have already driven yourself nuts. Use quality parts, dot your I's and cross your T's and you will be in business.
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Would still like to see some pics of your plumbing. I believe you mounted your pump in the engine bay. Not ideal. It'll pick up heat in there and will have to suck harder through the longer line going to it. It's ideal to have the pump as close to the tank as possible. I recently moved mine out of the engine bay as I was having issues.
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- #47
How would I route the fuel feed line if I mount the pump close to the tank. The stock hard line pops up right under the battery. That means would back track towards the tank to finally going to the EFI.
My pump is mounted on the frame rail just below the fuel tank. The lines run in their stock positions, under the battery, along the front of the engine and along the valve cover. Snap some pics of your setup. As was mentioned above, you’ve got to do this systematically and by the book.
Depending on the pump being used you could experience cavitation if your NPSH isn't correct. There should be a NPSH required spec for the pump, you will have to do a manual calculation for the NPSH available. The Holley manual references cavitation in the startup guide.
NPSH available must be greater than NPSH required or cavitation WILL OCCUR!!
NPSHavailable = (pressure in the fuel tank/specific weight of gasoline) + (height from inlet to pump) - (sum of losses)- (vapor pressure of gasoline/specific weight of gasoline)
The loss term is the sum of major and minor losses, the major due to friction in the hose (calculated using moody chart) and the minor are from fittings, entrance, and exit and can be taken from tables or from the fitting manufacturer)
You could probably ignore the minor loss term and see where your at. The major loss term is easily calculated.
Getting the pump closer to the tank will increase the NPSH available because the losses are smaller. The height of the pump wrt the tank will have little effect as this value is quite small in this application.
If you need help determining if you are experiencing cavitation you can shoot me a PM and I can help you calculate these values.
NPSH available must be greater than NPSH required or cavitation WILL OCCUR!!
NPSHavailable = (pressure in the fuel tank/specific weight of gasoline) + (height from inlet to pump) - (sum of losses)- (vapor pressure of gasoline/specific weight of gasoline)
The loss term is the sum of major and minor losses, the major due to friction in the hose (calculated using moody chart) and the minor are from fittings, entrance, and exit and can be taken from tables or from the fitting manufacturer)
You could probably ignore the minor loss term and see where your at. The major loss term is easily calculated.
Getting the pump closer to the tank will increase the NPSH available because the losses are smaller. The height of the pump wrt the tank will have little effect as this value is quite small in this application.
If you need help determining if you are experiencing cavitation you can shoot me a PM and I can help you calculate these values.
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- #50
I honestly just put the new pump right where the previous had another electric fuel pump. I am going to do a fuel pressure test here in a bit. but heres some photos. I'll try to take some better clear ones. The wires, and hoses, are kind of everywhere right now.
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- #51
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- #52
HERE IS AN AUDIO CLIP OF WHAT IT SOUNDS LIKE WHILE I PRIME AND ATTEMPT TO START THE FJ.FJ START ATTEMPT
Did you ever get an RPM reading on the display? It won't run unless the ECU is seeing RPM.
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- #54
No. It just keeps reading stall while in the run position, and when trying to fire.
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- #55
I ran the yellow wire from the Sniper harness straight to the (-) ignition coil. and it just keeps reading STALL
unless it sees that RPM there is no way it will run.
I'll check mine in about an hour and see if mine shows RPM while it cranks. Either way, yours should show RPM at least when it's sputtering. Like I mentioned, I'd log onto Holley Sniper forums and ask why youre not seeing RPM. If it is hooked up correctly, it is possible you have a bad Sniper ECU. Better to find that out now than spend any more time on it.
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- #57
Mine doesn’t even sputter long enough for the STALL to change to “syncing”
I’ll take a look at the Holley forum.
Thank you again for the assistance!
If the ecu is reading the signal from the negative side of the coil then it will get a rpm based off of the cylinder # parameter you entered in upon your initial programming. This is a pretty simple setup and it should be pretty easy to verify all the different ingredients for success.
Put a multi meter on the yellow wire and see what sort of voltage and continuity your getting. Audible continuity will be fine. Don't even worry about polarity, you just want to make sure you're getting an rpm input signal. Since it tires to start but doesn't it means your running off the prime only and the injectors never open.
Put a multi meter on the yellow wire and see what sort of voltage and continuity your getting. Audible continuity will be fine. Don't even worry about polarity, you just want to make sure you're getting an rpm input signal. Since it tires to start but doesn't it means your running off the prime only and the injectors never open.
In regard to your plumbing pics.
I got the base unit and not the kit but looking at the kit, it comes with 3/8 ID hose and I am sure the fittings on the pump and filters are also 3/8. Where you clamp the hose onto the existing hard lines is of concern. The stock hard fuel lines are 8mm which is almost exactly 5/16. Clamping a 3/8 ID hose onto a 5/16 tube is risky for sure. Also, you should not put a hose onto hard tube unless it is beaded. If you’re going to use hard line it should be 3/8 OD which also matches up with -6AN fittings.
I got the base unit and not the kit but looking at the kit, it comes with 3/8 ID hose and I am sure the fittings on the pump and filters are also 3/8. Where you clamp the hose onto the existing hard lines is of concern. The stock hard fuel lines are 8mm which is almost exactly 5/16. Clamping a 3/8 ID hose onto a 5/16 tube is risky for sure. Also, you should not put a hose onto hard tube unless it is beaded. If you’re going to use hard line it should be 3/8 OD which also matches up with -6AN fittings.
Hi Braden,
So I wanted to confirm you should be seeing an RPM on yours as you crank/no run.
I unplugged my fuel pump relay so it wouldn't start.
While cranking, but not, running mine showed about 200RPM. That's what I expected but wanted to be certain.
Until you get an RPM to show up on your display yours is not going to run.
It could be your ignition system, your wiring between the coil and the Sniper, or the Sniper itself.
I wouldn't worry about anything else until you can get your Sniper to see the engine RPM.
The fact that yours will briefly run after a hefty fuel prime makes me think your ignition system is working. And your fuel system is working, at least enough that it should fire up somewhat.
Sorry, can't help anymore at the moment.
B.
So I wanted to confirm you should be seeing an RPM on yours as you crank/no run.
I unplugged my fuel pump relay so it wouldn't start.
While cranking, but not, running mine showed about 200RPM. That's what I expected but wanted to be certain.
Until you get an RPM to show up on your display yours is not going to run.
It could be your ignition system, your wiring between the coil and the Sniper, or the Sniper itself.
I wouldn't worry about anything else until you can get your Sniper to see the engine RPM.
The fact that yours will briefly run after a hefty fuel prime makes me think your ignition system is working. And your fuel system is working, at least enough that it should fire up somewhat.
Sorry, can't help anymore at the moment.
B.
