Holley Sniper EFI/quadrajet

1-tonmudder

1-tonmudder

Doin my part to stir the pot.
Joined
Apr 17, 2005
Location
Greeneville TN
Look at putting a sniper EFI on jakes Caddi. The PO put a 600 CFM quadrajet on it trying to get a lill more mileage out of the 472 :shaking: so its already probably too small for the engine.esp considering it came stock w a 780,I dont think the current carb is gonna make it and a 780 replacement carb is $500 ish.Seriousily considering just biting the bullet and spending HIS money on a sniper set up.Its a all stock 71 Deville,future mods include getting it running and driving it.Its an all original survivor and he has no desire to change anything.The Sniper EFI is suppose to support 500 HP so it should be plenty.What the concensus on these kits,good.bad.ugly or indifferent??

Holley Sniper EFI 550-869K Holley Sniper EFI Quadrajet™ Master Kit - Classic Gold

Are you tired of rebuilding the 50+ year old Rochester™ Quadrajet® (Q-Jet™) on your classic Chevrolet, GMC, Buick, Oldsmobile, or Pontiac? The Sniper EFI Quadrajet™ is here to help! The first bolt-on spreadbore electronic fuel injected throttle body system that does not require any additional...
www.holley.com www.holley.com
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They are great. I've installed a couple.
TB flows a lot more than 780CFM. The fueling is what limits it to 500hp. But that won't be a problem in your case.

But they seriously need professional tuning, the "self learn" feature is shitty at best. Works great to get is started and drive it to the tuner, that's about it.

If you want to get fancy, get a dual synch dizzy and have it control timing too. You will definitely see a mileage improvement from that but it's more $$$$ and ABSOLUTELY needs pro tuning.
 
Not sure that it really matters, but FiTech just released one that looks more like a carb, and looks to remote mount the ECM. 30020 Go EFI Classic 650HP System - FiTech Fuel Injection If you are still using the factory air cleaner, not sure that you will be able to tell what's under it anyway.

I have installed a Sniper unit on a friend's bronco, and helped install one in a boat. I would say to be careful to make sure the signal wires are not running next to power wires, as EMI can be an issue.
 
You couldn't pay me to run a FiTech product.
And the price is similar enough with the Holley that I cannot understand why you wouldn't go with the proven, USA supported, system.
 
Ive got a few sniper efi setups now, the first one i used was fitech... don't waste your money the holley product is 10x better and fitech support is or was completely useless.
If you're going to do it, go sniper efi, in tank pump and timing control.
 
Tested a couple FiTech units at LEB…not a fan at all, and most customers that got them went back to carb, for various reasons, and we stopped selling FiTech. The Sniper kits are nice, the only issues I’ve seen out of them (aside from user error) are RFI issues, which Holley seems to refuse to acknowledge…but general fix is additional sheathing or additional grounding. Really seems hit or miss though, and I can’t seem to find a correlation to vehicle/routing/specific kit. A good group for FAQ’s and tips/tricks:

885BCD97-892B-4A91-AE47-E9CF6879C154.png
 
Bebop said:
the best thing you can do for that is to open the Holley harness, delete the unused wires, and route the power and signal wires in 2 different locations.
Just like @paradisePWoffrd said.
Click to expand...
I will never understand why these companies wont switch to a twisted, shielded cable like the industrial communication world has done for 20+ years.
You can essentially eliminate EMF interference with proper shielding.
 
Ron said:
I will never understand why these companies wont switch to a twisted, shielded cable like the industrial communication world has done for 20+ years.
You can essentially eliminate EMF interference with proper shielding.
Click to expand...

I'd say because it's more expensive and they're cutting costs everywhere they can and that in most cases it'll be fine as is.
I use proper shielded cables in the harnesses I build, but Holley only uses it on WBO2, Crank sensor and that's about it.
 
Bebop said:
You couldn't pay me to run a FiTech product.
And the price is similar enough with the Holley that I cannot understand why you wouldn't go with the proven, USA supported, system.
Click to expand...

braxton357 said:
Ive got a few sniper efi setups now, the first one i used was fitech... don't waste your money the holley product is 10x better and fitech support is or was completely useless.
If you're going to do it, go sniper efi, in tank pump and timing control.
Click to expand...

I hadnt used the FiTech. Good to hear some feedback. I liked how that one unit moved the ECM out of the throttle body.

The boat that I helped with, kept having EMI/RFI issues, and no movement of wires seemed to fix it. He finally got Holley to replace the throttle body itself and it seemed to fix most of the issues.

Next one I do, I will likely get some sleeves to help shield the control wires.

Also, just for info; if you are starting an engine for the first time, it is likely best to put a standard dizzy in atleast, if not use a carb to get timing and everything set correctly. Or maybe I just dont know what I am doing. We put a sniper and Dual sync on an engine that had never been fired, and it took some trials to get the timing set and it running correctly at first. At the end of the day, the bronco runs and drives great, and glad we went in tank pump and dual sync. The retrofit pump module was easy to install and works great.
 
I've been a subscriber hear for a while but haven't posted much or in a long time.

I'm glad I found this thread. I've considered a sniper 2300 system for my 360 powered CJ-7 over the past few years. If the same (or very similar) system can also be used on my boat then that could happen a year or so later. Both my boat which run a GM 4-cyl (volvo) system and my 360-CJ us a 2300 holley. Seemed strange that the nearly doubled displacement of the Jeep breathes through the seam carb as the boat when both are low RPM engines. But I am not looking for a fire-breathing V8 in this Jeep - just a smooth operating engine that is well mannered more often.

Both vehicles run nicely once they are up to temp. The Jeep has to be driven out of the garage pretty quickly after starting or my eyes will be watering pretty quick and occasionally gives me trouble during hot starts. The boat runs nice and starts easy when cold but I have to be really careful to keep it happy during the trasisiton form cold to hot and it often wants to run backward a lttle when I shut it down. The jeep is top priority - it sees a lot more use than the boat.

If any of you have installed in a CJ: is there an easy in-tank pump that fits easy into my tank? The previous owner cut an access panel over the sender unit so no tank-dropping to gain access.
 
CJKevin1984 said:
I've been a subscriber hear for a while but haven't posted much or in a long time.

I'm glad I found this thread. I've considered a sniper 2300 system for my 360 powered CJ-7 over the past few years. If the same (or very similar) system can also be used on my boat then that could happen a year or so later. Both my boat which run a GM 4-cyl (volvo) system and my 360-CJ us a 2300 holley. Seemed strange that the nearly doubled displacement of the Jeep breathes through the seam carb as the boat when both are low RPM engines. But I am not looking for a fire-breathing V8 in this Jeep - just a smooth operating engine that is well mannered more often.

Both vehicles run nicely once they are up to temp. The Jeep has to be driven out of the garage pretty quickly after starting or my eyes will be watering pretty quick and occasionally gives me trouble during hot starts. The boat runs nice and starts easy when cold but I have to be really careful to keep it happy during the trasisiton form cold to hot and it often wants to run backward a lttle when I shut it down. The jeep is top priority - it sees a lot more use than the boat.

If any of you have installed in a CJ: is there an easy in-tank pump that fits easy into my tank? The previous owner cut an access panel over the sender unit so no tank-dropping to gain access.
Click to expand...
Edelbrock makes a Pro Flo 4 that fits the 360 too. It's a more complete system but I'm not sure how well the Edelbrock FI compares to Holley

www.edelbrock.com

Pro-Flo 4 EFI Traditional 4150-Style Kit #35650 For 70-91 AMC 304,360,390,401

Edelbrock Pro-Flo 4 EFI kit #35650 for 1970-91 AMC 304, 360, 390, 401 c.i V8 engines. The EFI kit comes with a 4150-Style Single plane satin finish Victor Intake manifold and 35LbHr Injectors capable of 550 Max HP.
www.edelbrock.com www.edelbrock.com
 
CJKevin1984 said:
I've been a subscriber hear for a while but haven't posted much or in a long time.

I'm glad I found this thread. I've considered a sniper 2300 system for my 360 powered CJ-7 over the past few years. If the same (or very similar) system can also be used on my boat then that could happen a year or so later. Both my boat which run a GM 4-cyl (volvo) system and my 360-CJ us a 2300 holley. Seemed strange that the nearly doubled displacement of the Jeep breathes through the seam carb as the boat when both are low RPM engines. But I am not looking for a fire-breathing V8 in this Jeep - just a smooth operating engine that is well mannered more often.

Both vehicles run nicely once they are up to temp. The Jeep has to be driven out of the garage pretty quickly after starting or my eyes will be watering pretty quick and occasionally gives me trouble during hot starts. The boat runs nice and starts easy when cold but I have to be really careful to keep it happy during the trasisiton form cold to hot and it often wants to run backward a lttle when I shut it down. The jeep is top priority - it sees a lot more use than the boat.

If any of you have installed in a CJ: is there an easy in-tank pump that fits easy into my tank? The previous owner cut an access panel over the sender unit so no tank-dropping to gain access.
Click to expand...
You're gonna have to cut the tank to fit a drop in. Better remove it anyway to clean up after cutting.
Or use an inline external pump.
 
CJKevin1984 said:
If any of you have installed in a CJ: is there an easy in-tank pump that fits easy into my tank? The previous owner cut an access panel over the sender unit so no tank-dropping to gain access.
Click to expand...
I plan to make my own using an MTS fuel sender. Or Holley has a handful of options, including their own Sniper brand tanks.

Or use an external pump.
 
Holley has a pump for the CJ that drops in place of the stock sending unit but it’s only for the smaller 15 gallon cj tank. Not deep enough for the 20 gallon. It’s returnless, so less plumbing involved. Part number 12-307. External pumps don’t have a good place to be mounted on a cj or wrangler. You need it below the tank so it has a gravity feed of fuel. High pressure fuel pumps can’t suck fuel out of the tank. They’ll overheat and eat themselves alive. Put it in the tank, especially if you wheel. You can also get a universal in tank pump module from Holley or I think Aeromotive makes them too. Take a hole saw to the tank somewhere separate of the stock sending unit and drop it in. Cap the old sending unit hoses and just use it for your gas gauge.

The original MSD atomic fuel injection was/is very good. Either that or the Terminator X Stealth 4150 are my choice for best bang for your buck. I’d convert it to a 4bbl regardless. Snipers are great when they work right, but they’re picky especially with a front distributor engine like an amc or ford v8. Both the t-x and original atomic have remote ECUs so less chance of RFI. The ecu being on the throttle body puts it closer to a big source of interference and I’d avoid it if possible. Not to say it won’t work fine- plenty of folks do it, but I prefer to give myself the best chance of success possible when I do something important like a fuel/engine management system.
 
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I know this is kinda a derail, but does anyone know the factory ohm rating on the AMC sending unit? I have a 78 j10 with a AMC 360 that has a retrofitted gm TBI. It currently has a plastic fuel cell with E2000 pump mounted below it. Its only been through one pump in 10 years, but I really dislike the plastic fuel cell. I would like to swap it out for a factory tank (think jeep cherokee or chevy s10 blazer) maybe in the factory spare tire location. I'm looking for a tank that would work with the factory gauge and have an electric pump.
 
For a basic tbi system, I would recommend the Howell TBI. Pretty much plug and play and great reliability.
 
I will echo a lot of what @Buddy Holly mentioned. Pump mounting of an external pump sucks on a CJ. Mine is not correct and is noisy as hell. I got it low-ish but it is still less than ideal. I do plan to replace it with the part number mentioned above as I swap in the new engine and clean up some plumbing and wiring. That said, I have zero complaints on how it runs compared to the factory BBD carb. It can be further dialed in by someone who is good at tuning the fine parameters and reading data logs. Wire routing is key to reducing the RFI issues on the V8's. Less of an issue on the inline 6's as things can be split down each side of the block away from the ECU/TB unit. I did notice a small difference going from OEM plug wires to the MSD ones that were mentioned in the Sniper install instructions (I think that is where I got the PN). Whether that was a better quality wire, better shielding reducing any RFI issues or a combination of both, I cant confirm. But it does run better.
 
All things considered, the price of these systems are just too high compared to the benefits (for me). Also, this is an engine that I rolled the dice on for $200. Spending 5X that on fuel delivery doesn't make sense without a refurb.
 
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