Holley Sniper EFI (1 Viewer)

[thecrazygreek]

Look into the 2GC large bore.
way more of a stock carb profile, almost the same bolt pattern to the manifold.

I think the 2300 is popular because it was the only choice in the beginning.
But the 2GC large bore is the better fit.

 

[rflegal]

Almost 20 years on the same rig: I started with a stock carb, then weber, then to Projection 2DI, now to Sniper 2300. I will stay with the Sniper.

 

[peytonkristen]

Digging deeper into the Sniper EFI install.

The PO of my 40 installed the Weber carb. In the process he unhooked the charcoal canister and removed the separator and plugged all the lines. It would vapor lock occasionally until I vented the gas cap. It has run fine since, except for the usual carb issues.

Will this have any effect on the Sniper EFI?

 

[rflegal]

That's the way I'm running my '76 now - no charcoal, plugged lines. Runs fine.
'Coarse, no emissions inspections here either.

 

[TEQ]

I'm two days into driving my '78 with a Holly 2300. I did it because I had tons of drivability issues in the Utah altitude and struggled to find anyone in the SLC area who could confidently fix the carb. Yesterday I drove up to Alta and did a little wheeling to shake it down. Ran very well, although it's still "learning" and I'm not quite sure when it will be done learning. It seems to be running rich.

We used TRE in tank pump and the Mosely air cleaner adapter.

 

[kerplunk]

The PO of my 40 installed the Weber carb. In the process he unhooked the charcoal canister and removed the separator and plugged all the lines. It would vapor lock occasionally until I vented the gas cap. It has run fine since, except for the usual carb issues.

Correctly venting through the fuel seperator and charcoal canister should cut down on smell.
My '74 has an aftermarket plastic tank under the passenger seat, and pretty constantly smelled of fuel until I corrected the venting through the separator and charcoal canister.
And, from the other threads I've read considering this upgrade myself, I believe a fuel return line is also required with the sniper system (which was there on my '74 40, but is not used by my carburetor, and was all mucked up by a PO with a vent line attached).

 

[rlong]

As TEQ infers those of us living at say 5,000 - 6,000 ft that can readily be at 10,000 ft probably had a passion for anything fuel injected (mass air sensor) over carb fairly early on. Even a well tuned carb is already too rich at 10,000, then start bouncing around up a steep slope and you can have trouble ("it ran great last time"). Hense my obsession with EFI (and I was good with carbs), and now that Sniper is the easiest and cleanest "out of the box" it just tends to be many's choice. BUT if you like and understand them GM TBI is very functional with tons of support and vendors (you prolly want a custom burned chip, and might take one or two to get exactly what you want).

I have been watching Landcruiser, jeep, and hot rod forums in regards to Sniper installs and non-scientifically it seems that the "success rate" of Sniper is way higher than other efi systems over the years. And many of these guys don't even really understand how efi works or enjoy a good discussion of stoichiometric ratios through the RPM range!

 

[wngrog]

FYI - For all the Sniper 2300 peoples, be sure you have a backup pre & post fuel pump filter. If while driving your engine starts losing major power and the Sniper's AFR is high with a red box, then shuts down, this is a good sign of a clogged filter.

Yep. Been there

 

[wngrog]

There is a very thorough thread in the 40 section about installing snipers. A quick search should give you all the info you want.

Texas Red’s

 

[TEQ]

Texas Red’s

I am normally the one telling noobs to use search. But in this case I'm failing myself. I've found about a dozen threads in the 40's section on Holly Snipers but none of them are "very thorough about installing snipers." I must be missing something obvious, and my apologies in advance for that. But could you please just point me at the thread?

 

[wngrog]

I am normally the one telling noobs to use search. But in this case I'm failing myself. I've found about a dozen threads in the 40's section on Holly Snipers but none of them are "very thorough about installing snipers." I must be missing something obvious, and my apologies in advance for that. But could you please just point me at the thread?

Builds - Texas Reds - The Tale of Two Red 40’s

I stalled out when I realized I did not have any normal height greaseable shackles. The ones one the truck are 5” eye to eye. Stock are 3”. The OME greaseable are 3” so that keeps your caster good. This truck, not only has 3” taller springs in the front, it also has the aluminum caster shims...

forum.ih8mud.com

FYI, this truck did not like the Corvette return at all. The owner ended up pulling it out and running a normal return and it cleared up all of his issues.

 

[rflegal]

Builds - Texas Reds - The Tale of Two Red 40’s

I stalled out when I realized I did not have any normal height greaseable shackles. The ones one the truck are 5” eye to eye. Stock are 3”. The OME greaseable are 3” so that keeps your caster good. This truck, not only has 3” taller springs in the front, it also has the aluminum caster shims...

forum.ih8mud.com

FYI, this truck did not like the Corvette return at all. The owner ended up pulling it out and running a normal return and it cleared up all of his issues.

I was wondering about that return filter. Thanks for the feedback, I'm running full return lines.

 

[rflegal]

Mockup and prepping for reinstall - just got some clearer shots. I'll remove for header rewrap and block install. My Sniper is mounted 90 degrees on an Offy 4bbl manifold. 90 to clear the hydroboost unit. Actually fits quite well.

 

[wngrog]

Good Lord why do you want a 4 barrel on that 2F??

 

[rflegal]

Good Lord why do you want a 4 barrel on that 2F??

The manifold is 4. The Sniper is a 2, 2300.
Beats the choked down adapter approach and flows great, runs well.
Look at the manifold again. Essential a 2300 intake with a 4 bbl flange. As I said, been running it since '02 with a Projection 2Di. Hence the req'd realastate.
Also, notice how the horizontal runner lines up almost perfect with the 2300 butterflies for distribution. No lag experienced from open plenum with efi.

 

[wngrog]

Sweet. Good idea. Sorry for the confusion

 

[rflegal]

The manifold is 4. The Sniper is a 2, 2300.
Beats the choked down adapter approach and flows great, runs well.
Look at the manifold again. Essential a 2300 intake with a 4 bbl flange. As I said, been running it since '02 with a Projection 2Di. Hence the req'd realastate.

Sweet. Good idea. Sorry for the confusion

No worries. I don't know if you can even get these Offy's these days. I understand they're a rare beasty.

Sweet. Good idea. Sorry for the confusion

No worries.

 

[workingdog]

Yes, you have to run a return with a sniper, and it's crucial that the return have no back pressure at all. Needs to be free flowing into the tank. I ended up putting a basic CAT on my rig to clean up the smell. Smell is a real challenge for these rigs.

 

[rflegal]

Yes, you have to run a return with a sniper, and it's crucial that the return have no back pressure at all. Needs to be free flowing into the tank. I ended up putting a basic CAT on my rig to clean up the smell. Smell is a real challenge for these rigs.

Interesting. I've never noticed a smell. But then, I'm topless....

 

[wngrog]

Yes, you have to run a return with a sniper, and it's crucial that the return have no back pressure at all. Needs to be free flowing into the tank. I ended up putting a basic CAT on my rig to clean up the smell. Smell is a real challenge for these rigs.

I needed one on my FJ60 with the AFI so it’s there but my 55 does not have one and it’s not noticeable.