Sniper install - '88 GWag

For everything related to using Fuel Injection in an FSJ.

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Milktruck
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Sniper install - '88 GWag

Post by Milktruck »

Ho Ho Ho!

I made the decision right before Christmas that I need to go all in and fix the things that are bugging me about my GWag before I relegate it to a semi permanent secondary status. I've pretty much stopped driving it b/c I have had repeated fueling issues, and my average drive is over an hour. Not fun running with full troubleshooting gear. Never mind the fact that I can't get anyone to ride with me in it b/c they fear being stranded. They ain't stupid.

I just received a couple of boxes from efisystemspro and will be doing a Sniper install. Went with the dizzy, ignition and coil and await an intake manifold. As I am getting deliveries, I am wondering where folks have been drawing switched power for their installs? I am seeing some posts that say the 10AWG from the Duraspark box is preferred. Seems that would make sense.

Wish me luck, I've already spent more than I want to, but I've been dreaming fuel injected dreams for a couple of years now.
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille
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ghcoe
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Re: Sniper install - '88 GWag

Post by ghcoe »

Watching, since it sounds like you will have yours in before mine.
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1977 Jeep Cherokee WT
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dbabicky
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Re: Sniper install - '88 GWag

Post by dbabicky »

I am staying tuned in also. I have a complete Ron Francis wiring harness and Holley Sniper in my shed waiting for warmer weather to install. These Wisconsin winters suck when you have an uninsulated and non-heated shed. I need to get my ass moved to West Texas ASAP !!!

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

So yesterday I got some wrenching done...

https://www.icloud.com/sharedalbum/#B0J5idkMwdFeHy

I’ve still gotta clean the mating surfaces for the intake and valve covers. I swear every bolt was looser than it should’ve been. (At least that made for easy disassembly) Thread locker will be part of the installation process.

Anyone have knowledge about power source for the Sniper? I’m still looking at that Duraspark box thinking that I’ll pull power from there.
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille
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Hspencer
Posts: 164
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Re: Sniper install - '88 GWag

Post by Hspencer »

I pulled switched power from the yellow wire going to factory ignition module. If you’re using the hyperspark ignition you’ll need to install a diode in the brown resistance/exciter wire going to the alternator to prevent engine run on. Apparently there is enough power back feeding through it to keep a run signal to the Holley module and the engine won’t shut off with ignition switch.

Tgreese helped me out with this. Here’s a link to the proper diode he shared with me.


https://www.allelectronics.com/item/d61 ... ode/1.html



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1988 GW
1984 Wagoneer(SJ)
2008 JK
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Hspencer
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Re: Sniper install - '88 GWag

Post by Hspencer »

One other thing. When I went to swap the distributor gear from the old distributor (most everyone recommends this) the holes on the old gear didn’t line up on the new distributor shaft. With the gear installed and the roll pin pushed partially in the hole on the opposite side of the gear was about 1/16” off, tried rotating 180° same thing.

I called Holley and the tech said as long as both cam and distributor gears were the same material it wouldn’t be an issue.

I’ve read serval accounts of the gears failing rather quickly after installing a new distributor gear to an old cam gear.

I went ahead and installed it with the new gear and after 100 miles or so I pulled the distributor and both gears look good. Unfortunately other issues have me pulling the engine to be rebuilt so the cam gear will get replace anyway.

I would do some research and make your own decision, I can’t say what’s right either way.

Good luck with the install


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1988 GW
1984 Wagoneer(SJ)
2008 JK

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

Thanks for the tips and links Hspencer. I'll read up on the distributor gear. Makes sense. Also the diode.... appreciate it
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille
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Hspencer
Posts: 164
Joined: Wed Mar 20, 2019 5:35 pm

Re: Sniper install - '88 GWag

Post by Hspencer »

Happy to help


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1988 GW
1984 Wagoneer(SJ)
2008 JK

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

Pulled the trigger and ordered an in-tank fuel pump from Novak. They had one ready to go and I'll have it in hand by the weekend. I've been going back and forth about doing this, but just don't want to mess with an electric pump sitting externally. That is what I've got now, and it was WAY better than mechanical FP, but I've already had to replace it once and want to get away from the noise. I'll be eating ramen for awhile...
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille

ShagWagon
Posts: 702
Joined: Tue Apr 19, 2016 8:13 pm

Re: Sniper install - '88 GWag

Post by ShagWagon »

Be sure to measure it to the bottom of the tank. You will need to add about 2.5” to the pickup to reach the bottom. Or else it will run out at about a little more than 1/4 tank,left.
87 Grand Wagoneer Rebuilt 360 by S&J, Fitech GO EFI 600, Novak in-tank fuel pump, Skyjacker Hydro 4" lift, BFG AT KO2 30", Dynamax Muffler, MSD distributor, MSD ignition, Edlebrock perf 4bbl intake, Elgin perf cam, Oil tube mod, Roller rockers, chrome molly lifters, HD alum radiator, Powermaster 150/100 alt, Alum HD water pump, Serhills tailgate harness, Cowl screen mod, Evil Twin grab handles, Rstep's custom AMC door lock knobs, all electrical works.

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

Thanks shagwagon! I learned that the hard way with a prior sender replacement. Drove me crazy
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

Got to wrench today. Manifold, new valve covers and dizzy installed. It’s gonna be nice losing so much vacuum spaghetti!
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

Yesterday was crappy, but added the ignition box, coil, and got the Sniper body on the manifold and vacuum plumbed. Can't believe that the linkage didn't come with fittings for the price of that kit. Picking that up tomorrow. The engine sure looks better with all that shiny new. I mounted the ignition box behind the battery and the coil on the opposite side between the fluid jugs and cruise control. Pretty discreet. I snapped a photo before I finished up for the day:

https://www.icloud.com/sharedalbum/#B0J5idkMwdFeHy
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille
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ghcoe
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Location: SW Idaho

Re: Sniper install - '88 GWag

Post by ghcoe »

Looking good!.
SW Idaho Overlanding Facebook: https://www.facebook.com/SWIdahoOverlan ... page_panel
SW Idaho Overlanding Youtube: https://www.youtube.com/channel/UCYuRx2 ... wVwZJ5oztg
1977 Jeep Cherokee WT
All-Terrain T/A® KO2
Safari Kit
Factory Brush Guard
Factory Tire Carrier
Custom Roof Rack

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

Anyone have ideas for the throttle cable and cruise control bracket? Seems like the stock does not transfer well.
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

Everything connected/installed. I powered on the system and configured, but no spark. Hmm..... Turns out I forgot all about that little firmware upgrade for the Hyperspark Distributor. Waiting for an SD card reader so that I can do the upgrade. The in-tank fuel pump was such a pleasure to prime and get pressure. Whisper quiet
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

Success! Got home today, updated firmware, checked connections and it fired up when I turned the key! I’ve got a laundry list of detail work, but it runs better now than when it was carbd.
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille
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Hspencer
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Re: Sniper install - '88 GWag

Post by Hspencer »

Congrats! The only thing I don’t like is having to wait for the computer to boot before starting. Other than that I love the sniper/hyperspark setup. What did you end up doing about the distributor gear?


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1988 GW
1984 Wagoneer(SJ)
2008 JK

Topic author
Milktruck
Posts: 89
Joined: Fri Feb 10, 2017 8:02 pm
Location: North Carolina

Re: Sniper install - '88 GWag

Post by Milktruck »

I swapped the gear b/c it was a direct fit. Thanks for the note on that. It seems that the manufacturer suggests swapping only if there is a materials mismatch. That said, it was a 5-minute process and keeps the wear pattern the same. I’ve got the diode ready to put inline if I have a run on issue. So far it hasn’t cropped up.
1988 Jeep Grand Wagoneer backdating to 78/88 blend
5.3L LS/3" Lift/Bilstein Shocks/Boobie Grille
User avatar

Hspencer
Posts: 164
Joined: Wed Mar 20, 2019 5:35 pm

Re: Sniper install - '88 GWag

Post by Hspencer »

Nice, glad it’s working out!


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1988 GW
1984 Wagoneer(SJ)
2008 JK
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