Holly Sniper EFI issues or NOT?

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Very clever indeed. Tho I must say I have no issues with the ECU (yet). I got issues with the device for sure, Most due to my lack of knowledge in the first place. Like not knowing that exhaust needed be airtight (they do not tell you that in the install vids). or modify Masda parts to move the sensor outwards, leading to much smoother AFR readings and not having to replace the fried sensor every 6 months...
But one thing that did fix it really good is to override the internal regulator (or better said, ditch that dang badly designed thingy),
and install an external one. Now with steady pressure, no more over rich conditions with pressure going in the 70's psi and most other weirdnesses are gone. I saw that the version 2.0 also use an external one too now.
 
I went with Aces kill shot efi master kit for my Cleveland waiting on it to come in. The eco is a standalone unit that can be mounted away from the motor and throttle body reducing heat. I would say do a little research on aces. They also self tune to performance upgrades. I have watched a lot of videos and read one Aces kill shot kit. I ordered the master kit for $1580
I also bought the aces killshot with distributor but not quite ready to install. I went with the Holley 340lph fuel pump for foxbody mustangs as the top plate perfectly fit the vent hole on our tanks, so no cutting. Only modification I had to make was to move the pump about a half inch up to adjust for depth. I bought a new fuel tank as mine was starting to rust inside. I will install very soon and will take lots of pictures. My original fuel line is in good shape so will be using it for a return line and bent a new 3/8 line for supply. Current hold up is moving the battery to trunk.
 
I also bought the aces killshot with distributor but not quite ready to install. I went with the Holley 340lph fuel pump for foxbody mustangs as the top plate perfectly fit the vent hole on our tanks, so no cutting. Only modification I had to make was to move the pump about a half inch up to adjust for depth. I bought a new fuel tank as mine was starting to rust inside. I will install very soon and will take lots of pictures. My original fuel line is in good shape so will be using it for a return line and bent a new 3/8 line for supply. Current hold up is moving the battery to trunk.
What are you going to do for a vent?
 
I also bought the aces killshot with distributor but not quite ready to install. I went with the Holley 340lph fuel pump for foxbody mustangs as the top plate perfectly fit the vent hole on our tanks, so no cutting. Only modification I had to make was to move the pump about a half inch up to adjust for depth. I bought a new fuel tank as mine was starting to rust inside. I will install very soon and will take lots of pictures. My original fuel line is in good shape so will be using it for a return line and bent a new 3/8 line for supply. Current hold up is moving the battery to trunk.
As an alternative to moving the battery to the trunk consider replacing your battery with a newer Lithium one. They are expensive but moving the battery to the trunk is not cheap either. This will save you from adding long and heavy battery cables.
 
As an alternative to moving the battery to the trunk consider replacing your battery with a newer Lithium one. They are expensive but moving the battery to the trunk is not cheap either. This will save you from adding long and heavy battery cables.
I have already ran 0/1 awg cables, honestly trying to declutter the engine bay. These cars for being old have no space in the engine bay. Let alone the advantage of moving some weight to the rear. On the bright side, the wire run to the gas tank will be short.
 
Here’s where I ran my ECU, inside the passenger kick panel. And, the original trim over it still works.

View attachment 92261View attachment 92262
I am going back and forth between putting the ECU in the car or mounting it where the vapor canister was. The benefit to putting it where the vapor canister was is already have 3 studs to mount to and it would be deep enough to be mostly hidden when hood is open. Also would mean a lot smaller hole going into the car as it would only be the CAN cable. Just would make a simple plate out of ABS for the ECU to mount on. Plus the Aces ECU has status LEDs so I want to be able to see them without contorting my body.
 
Hello everyone,
Its been a while since ive been on the forum. Found myself reading questions and answers for 2 hours last night. Glad to be back.
I wanted to ask what problems if any that you folks have had with the Holly Sniper fr 4150 master kit?

I stopped into our local hot rod shop Kennys hot rods and spoke with them about the install. They have a large following and great reputation over the last couple of decades in town. There master tech warned me that the sniper has issues with Ford motors. He went on to say that the ecu in the bowl is to close to the distributor, It send wacky electronic waves to the ecu and makes lots of hickups. Often making the engine stutter and almost stall. Ive already purchased the fr4350 efi master kit and now Im bummed if I cant install it due to this manufacturing error. I already have the Msd 6al installed and it works great.

Hot rod shop recommends the Holly Terminator x stealth because the ecu is mounted under the dash. Thus solving the wave interference from the distributor and ecu.

To those who have installed the sniper to there 351c engines? please tell me how did it work out for you? I cant afford to do this install and then tear it out because it doesnt work?

Thank you in advance for all your help! I appreciate any and all help!
Rod
To simplify things, myself with my 72 and my friend with his 67 Stang both have Snipers. We both eventually changed out the oem distributor to Holley distributors. I used the dual sync distributor that is a no brained to install and my 351C runs great. My friend installed a Holley Hyperspark distributor in his 67. His runs very well. It’s a matter of choice which direction. The cheaper way is the latest sniper with the relocated controller. I think the better way is using an updated distributor that syncs well with the sniper and has no open contacts.
 
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To simplify things, myself with my 72 and my friend with his 67 Stang both have Snipers. We both eventually changed out the oem distributor to Holley distributors. I used the dual sync distributor that is a no brained to install and my 351C runs great. My friend installed a Holley Hyperspark distributor in his 67. His runs very well. It’s a matter of choice which direction. The cheaper way is the latest sniper with the relocated. I think the better way is using an updated distributor that syncs well with the sniper and has no open contacts
 
Very well said. I have the same set-up in our 72 351C, sniper & hyperspark! works great, no interference issues.
 
Thanks for the reply!
Im looking for reliability mostly but a bit better fuel economy or cheaper gas would be nice ( maybe vote in someone who gives a crap). LOL I get 6 mpg.
Currently I have a eldabrock performer 4v intake with a QFT carb, hooker headers, a little larger cam. Only 300 hp and 300 ft pds of torque. I drive it daily as weather permits. I restored the whole car so I show it as well.
Gears are 350 posi with a FMX tranny all are rebuilt. Engine has msd 6al electronic ignition.

I figured I was all set to install until I was told by Kennys rod shop to send it back.
6 mpg something way out of whack i small block with with 2 Holley 4V carbs on and got 15mpg around town
 
Hello everyone,
Its been a while since ive been on the forum. Found myself reading questions and answers for 2 hours last night. Glad to be back.
I wanted to ask what problems if any that you folks have had with the Holly Sniper fr 4150 master kit?

I stopped into our local hot rod shop Kennys hot rods and spoke with them about the install. They have a large following and great reputation over the last couple of decades in town. There master tech warned me that the sniper has issues with Ford motors. He went on to say that the ecu in the bowl is to close to the distributor, It send wacky electronic waves to the ecu and makes lots of hickups. Often making the engine stutter and almost stall. Ive already purchased the fr4350 efi master kit and now Im bummed if I cant install it due to this manufacturing error. I already have the Msd 6al installed and it works great.

Hot rod shop recommends the Holly Terminator x stealth because the ecu is mounted under the dash. Thus solving the wave interference from the distributor and ecu.

To those who have installed the sniper to there 351c engines? please tell me how did it work out for you? I cant afford to do this install and then tear it out because it doesnt work?

Thank you in advance for all your help! I appreciate any and all help!
Rod
The only issue is with an electronic igniter in the distributor. A Pertonix igniter will send RF interference to the Sniper because of the positioning of the electronic components of the Sniper in the front and in close proximity to the distributor. I solved that issue by installing a dual sync distributor by MSD/Holley or you could go with the Hyperspark. A marriage made in Heaven! Problem solved!
 
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The only issue is with an electronic igniter in the distributor. A Pertonix igniter will send RF interference to the Sniper because of the positioning of the electronic components of the Sniper in the front and in close proximity to the distributor. I solved that issue by installing a dual sync distributor by MSD/Holley or you could go with the Hyperspark. A marriage made in Heaven! Problem solved!
Fully agreed!

I had the same issue. Now my 72 - 351C has all the sniper setup and in tank fuel pump.
Here, in Brazil, all fuel has 27% of ethanol, and although this, the sniper work flawlessly.
 
Fully agreed!

I had the same issue. Now my 72 - 351C has all the sniper setup and in tank fuel pump.
Here, in Brazil, all fuel has 27% of ethanol, and although this, the sniper work flawlessly.
Does the sniper have an ethanol content detector? The stoichiometric AFR for normal gas is 14.7. For gas with 10% ethanol is 14.3. With 15% ethanol, its 14.1.

I assume for 27% ethanol, you would be looking at something closer to 13.5 AFR for cruise and 12.5 under load. Does the sniper know what gas you're using? If not, it seems like it would try to run lean.
 
Does the sniper have an ethanol content detector? The stoichiometric AFR for normal gas is 14.7. For gas with 10% ethanol is 14.3. With 15% ethanol, its 14.1.

I assume for 27% ethanol, you would be looking at something closer to 13.5 AFR for cruise and 12.5 under load. Does the sniper know what gas you're using? If not, it seems like it would try to run lean.
It doesn’t, but I think you can add one.

I thought 10% was 14.1.

Either way if it is always 27% just adjust the target numbers and it will create a learn table to see what is needed. If you are tuned you can do a global fuel map change as long as you do the same to the target or it will learn to revert back to what you have
 
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