Holley Sniper 2 barrel conversion (1 Viewer)

[BrianSanDiego]

Since this seems to be the Sniper info thread and I've posted a lot of stuff here so far, I want to add something else so everyone considering this is aware.

I had what I thought was a fuel injector go bad. One of 4 stopped firing altogether. I called Holley about buying a replacement injector and was told that they don't sell the injectors separately, that I would need to send the unit in for service (4 new injectors) at a cost of $200. I've also heard that Holley doesn't sell ECUs separately. The rest of the parts are available. TPS, IAC, O2 sensor, and coolant temp sensor. I've had to replace a couple of those sensors because Holley seems to be using less expensive components for these. Quality replacements are not very expensive but it's a PITA and unnecessary. I'm a little concerned about future support for the Sniper if this is their current business model ... not all parts available for this system.

The problem with my injector seemed to be a bad connection at the wire connector, the plug isn't retained very well, and it seems to be a recurring problem. Easy fix with a little zip tie or a spot of glue. One guy is talking about 3d printing up little plastic retainers, something that Holley should be taking care of, obviously.

I just wanted to get this out there for anyone considering this system.
Brian.

 

[DomSmith]

^^^ This is disappointing but not too surprising.

Brian you probably remember a decade ago or more when I was running the old pro-jection system. It seemed like the support and replacement parts were an issue then.

I hope this ends up working out better for others as it seems like a decent option but it appears Holley may not have improved in this critical area.

 

[BrianSanDiego]

^^^ This is disappointing but not too surprising.

Brian you probably remember a decade ago or more when I was running the old pro-jection system. It seemed like the support and replacement parts were an issue then.

I hope this ends up working out better for others as it seems like a decent option but it appears Holley may not have improved in this critical area.

I do, I still have a part or two that you gave me.
The Sniper setup really is a nice system, but that whole thing about wanting me to send it in, instead of selling me the part, really chaffed-my-hide, as the cowboys say. And it wouldn't cost them much to include quality sensors instead of cheapies.
B.

 

[mrboatman]

So far I`m doing good. Got my charging system system straighten out so no now i`m getting 13.6 volts steady now.
JP

 

[BrianSanDiego]

Hello Sniper people,
I just stumbled upon a video that very thoroughly explains what it requires to allow Sniper timing control on a Large-Cap HEI distributor. I'll probably give it a try sometime in the near future. Interesting and informative and not me in the vid.

 

[snivilous]

Just ordered my 2 barrel sniper master kit from Summit! $1078 shipped, should be here tomorrow or Friday. For some reason last year my '77 started running insanely rich, and the carb as rebuilt less than 5 years ago, so it was either send it off or go EFI. The carb couldn't go up a small incline offroading without choking away, plus there's lots of elevation change where I live, and carbs are just a pain to begin with. I'll post on here with how it goes, I'm assuming I'll have to machine some brackets and plates. If I'm lucky maybe I'll end up taking the 40 to Moab next week instead of riding in my buddy's truck, we'll see!

 

[mrboatman]

Very easy install and you won`t be disappointed. Very nice upgrade !!
JP

 

[snivilous]

Trying to take a lot of photos to ease the pain for anyone in the future. Again, I ordered the Holley Sniper EFI 2300 Two-Barrel kit (550-849K) and nothing else. First two pictures are what showed up in the box, one is the Sniper EFI on the left, and the right is the rest of the "master install kit", ie fuel pump, fittings, hose, etc. I already have a fuel cell mounted in the back of my FJ40 (original tank was all nasty and annoying so opted for something easier and larger capacity), so for simplicity's sake I will be doing an external fuel pump. I already have an external electric pump to serve as a backup to the stock mechanical, and for better or worse have had lots of bad experience with aftermarket pumps so the ease of having the pump externally mounted where it can be swapped out in minutes is nice.

Anyways moving on, I didn't have an adapter or anything and from what I could tell no one makes one, so I just made one. My first attempt was pretty fast, and I didn't realize the Holley isn't symmetric left to right so the spacer didn't line up correctly. I fixed that as well as made some other tweaks on the second one. It's nothing fancy, initially I was going to use the stock studs but socket head cap screws were easier and then I used 5/16" bolts for the Holley side. I don't know what you call the airflow chamber, but the FJ is smaller in size than the Holley so I just did a loft feature between them, and then did 0.050" step downs on the mill and cleaned it up a bit with a sanding wheel. I then realized there's a bolt that seems to go through the intake manifold and holds coolant in, not sure what it does but I ended up machining a pocket on the back side that goes over the head of that bolt and then also had to do a bit of a cut to clear the intake manifold where it starts to rise up near the engine. Point being, it's nothing fancy but should work fine.

If someone wants one of these, I can make more (though I am NOT a machinist by any stretch, I just have a little cnc I put together for prototype parts for work) OR figure it out yourself OR here is the .STEP file for CAD and do what you want with it:

Anyways, everything bolted up great! The throttle linkage plate is a little close to the adapter plate, though it clears fine. I have to take it back off and tighten that weird coolant bolt, so will probably clearance that side on the mill really fast just to be safe.

 

[snivilous]

The exhaust O2 sensor is super simple, they give you a plate that's threaded so all you have to do is drill a 3/4" hole and place the plate on it and clamp it down (all of that minus the drill bit comes with the kit). While that sounded nice and all, I cut the plate down and just welded it on. It says the O2 sensor should be at least 10deg above horizontal, so I just did it smack on the top. This also happened to be the spot that had the most clearance under the truck. I have the wires just come up and follow the speed sensor cable and it works out really nice, and lots of room to reach the sensor to remove it in the future.

As for the coolant sensor, I was kind of worried where to put it. But amazingly, there seemed to be a coolant sensor already that was in the bottom of my thermostat housing. It didn't go to anything, and I doubt it was stock but maybe? I was hoping to go into the bottom of the thermostat housing anyways, so it worked out great since i just pulled that out and the new one threaded right in!

So the remaining tasks at this point is plumb the fuel system, wire everything (which is essentially just plug together), and then the biggest part will be adapting the throttle linkage setup to the Holley and adapting the Holley to the stock air intake (though I think that will be pretty straightforward). I'll start on that tomorrow and we'll see how it goes!

 

[thecrazygreek]

I installed this system not too long ago. Some tips in my thread. One thing the manual recommends is that you do not install the water temp sensor in the thermostat housing. Anyhoo, thought I would throw it out here...

Builds - My Holley Sniper EFI kit install into my 1978 FJ40

Hello all... Last June I installed an AFI tbi kit. It was the complete kit with electronically controlled dizzy. It was not the self learning kit. It was a lot of work to get installed but was absolutely wonderful once it was up and running. Fast forward to early December and it started giving...

forum.ih8mud.com

 

[snivilous]

I installed this system not too long ago. Some tips in my thread. One thing the manual recommends is that you do not install the water temp sensor in the thermostat housing. Anyhoo, thought I would throw it out here...

Builds - My Holley Sniper EFI kit install into my 1978 FJ40

Hello all... Last June I installed an AFI tbi kit. It was the complete kit with electronically controlled dizzy. It was not the self learning kit. It was a lot of work to get installed but was absolutely wonderful once it was up and running. Fast forward to early December and it started giving...

forum.ih8mud.com

Huh, I didn't see that anywhere but maybe I missed it. Do you know why? My bet is people put them on the wrong side of the housing and then don't get an accurate reading when the thermostat is closed, at least that was my reason for not wanting to mount it on the top side. Unless there's some super bad reason not to, I'll leave the sensor for now until it has an issue.

 

[Downey]

Snivilous, so you evidently didn't know about my FiTech/Sniper installation kits ??? These kits include the machined adapter, re-machined 8mm screws, fuel pump block off plate, weld-on 02 bung, temp sensor adapter, a throttle cable mounting bracket, and a 6 3/8" diameter "Fuel Injection" air cleaner that clears your brake master cylinder.

 

[FJ60Cam]

I’ve talked to the engineer(s) at Holley a few times about this system. As long as the temp sender reads 160+, you are good.

160 is the magic temp where the self learning system writes to permanent memory. It still controls fueling below that, it just doesn’t ‘learn’.

Another good spot, if you don’t have an open NPT plug on the top of the head, is the block drain. The temp sender will thread into that, and the wire length is just right.

I usually have to add wire to put it in the thermo housing to avoid draping wire over the exhaust manifold.

 

[snivilous]

Snivilous, so you evidently didn't know about my FiTech/Sniper installation kits ??? These kits include the machined adapter, re-machined 8mm screws, fuel pump block off plate, weld-on 02 bung, temp sensor adapter, a throttle cable mounting bracket, and a 6 3/8" diameter "Fuel Injection" air cleaner that clears your brake master cylinder. View attachment 1954272

Wow, that would've been really handy to know about haha. All I saw was the old Holley adapter plate you made. Oh well, too far gone now plus this is fun

 

[snivilous]

Well since I seemed to be behind the game and everyone already knows how to do the conversion, let's just jump ahead and say it runs and fired right up! I ended up getting a generic throttle cable from Summit and making two brackets, the stock linkage was gonna be a pain to retrofit. I also ended up following Downey's idea with a different air cleaner, which looking at his pictures now I think we got the same one haha. Also I concede thecrazygreek is 100% right, I found it in my manual where it says not to run the temp sensor in the thermostat housing. I even went to swap it with one of the head ports, but the probe on the sensor is so long it wouldn't fit without spacing it up and I didn't want an air bubble so went back to the thermostat housing. Well unbeknownst to me, what I've concluded is the thermostat is after the radiator and not before (unless there's some other reason) so the sensor took forever to heat up and then maxed out around 153F, so it didn't get hot enough to adjust the idle and I didn't want to drive it around. I'll let it cool down and move the sensor tomorrow, I'm thinking I'll swap out the stock sensor since it's nearly useless anyways and hopefully there's some depth in that port so the probe won't hit anything.

Obviously still need to clean up wiring and some other little things, but it fired up and everything seems to check out so far! I'll drive it a bunch tomorrow and see how it does. Thanks for this thread and the advice in it! The truck already seems way better off without the carb!

 

[snivilous]

Update on the coolant sensor, I moved it where the stock sensor is and rhe reading didn't change at all. I was suspicious the sensor was faulty and read that they can be as much as 20F off, so I found a replacement one (same thing as a 4.8L sensor) and bought that and put it back in the thermostat housing. No difference, both sensors read the same thing. Found some other people who have colder running vehicles and learned that you can adjust the Learning temperature, if you go into advanced tuning and fuel you can adjust the enrichment % at whatever temperature. Learning happens when the enrichment hits 100% (ie it's not richened for colder conditions) which is stock 160F. I changed my so it hits 100% at 120F since it takes forever to get past 140F and 150+ is a miracle.

I guess a lot of people have similar things happen, or they'll get on the freeway and drop to like 150F and it'll stop learning. This also makes sense with everything I've experienced and my temps the whole time have matched up with what my IR thermometer reads on the coolant hose. With the fuel settings changed it went right into learning mode and everything seems to be working well now.

 

[AlaskanWheeler]

@Downey, you ought to bring back the ol cast aluminum Holley filter...

 

[Downey]

@Downey, you ought to bring back the ol cast aluminum Holley filter...

I wish I could, the new aluminum foundry wanted more for the raw castings than the whole completed air cleaner assembly could sell for- - -eeerrrrrrr.

 

[BrianSanDiego]

I'm curious if the stock air cleaner would fit on this version of the Sniper..

Holley Sniper EFI 550-858 Holley Sniper EFI BBD for 1971-1986 Jeep CJ - Shiny

Introducing the Sniper EFI BBD, for Jeep CJ's! The Sniper EFI BBD will be right at home on any 258ci powered trail rig, or weekend cruiser. Not only does the Sniper EFI BBD offer superior throttle response and WOT power over the carburetor, but you can also gain timing control! Put an end to...

www.holley.com

 

[Dustin Messina]

I'm curious if the stock air cleaner would fit on this version of the Sniper..

Holley Sniper EFI 550-858 Holley Sniper EFI BBD for 1971-1986 Jeep CJ - Shiny

Introducing the Sniper EFI BBD, for Jeep CJ's! The Sniper EFI BBD will be right at home on any 258ci powered trail rig, or weekend cruiser. Not only does the Sniper EFI BBD offer superior throttle response and WOT power over the carburetor, but you can also gain timing control! Put an end to...

www.holley.com

View attachment 1967429

With a Mr. gasket adapter you can run a factory air cleaner. Just takes a little bit of tweaking.