Holley Sniper 2GC to 2F Install using Mosley Motors adapter
- Thread starter KY Longhunter
- Start date
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@wngrog Thanks for taking on the challenge! Probably should have started with that step, but I have learned plenty along the way!
Actually, looking forward to seeing how this ends up… it seems to have defied the standards and seems to me like it ain’t the Sniper but something it is tied into
@desmocruiser - How comes it? I found your thread while dealing with my own Sniper EFI issues.
I made two trips to GSMTR with a Sniper that would 'act a fool' on the traile, then run fine on the road - until it wouldn't run with ANY load on it. I absolutely feel for you. This year, was wheeling, @ The Carolina Relic Run, hit a small drop, and the truck stalled.... and WOULD NOT START. Went through everything: coil (tested bad, then good, replaced anyway), dizzy (found a loose wire on the pickup plate, repaired - tried to replace with a new DUI - but didnt realize it had mechanical advance spring to remove, removed, back to normal dizzy ), Sniper (found wire inside pinched, repaired).... lots of issues but never a resolution.... until replaced Coil, Dizzy, wires, and (physically) reset timing and retuned Sniper...
Let us know how you're doing.... #InquiringMindsWantToKnow
I made two trips to GSMTR with a Sniper that would 'act a fool' on the traile, then run fine on the road - until it wouldn't run with ANY load on it. I absolutely feel for you. This year, was wheeling, @ The Carolina Relic Run, hit a small drop, and the truck stalled.... and WOULD NOT START. Went through everything: coil (tested bad, then good, replaced anyway), dizzy (found a loose wire on the pickup plate, repaired - tried to replace with a new DUI - but didnt realize it had mechanical advance spring to remove, removed, back to normal dizzy ), Sniper (found wire inside pinched, repaired).... lots of issues but never a resolution.... until replaced Coil, Dizzy, wires, and (physically) reset timing and retuned Sniper...
Let us know how you're doing.... #InquiringMindsWantToKnow
It’s getting a new motor. New Sniper. New DUI. New O2.
@ErikinSC
Sorry to hear you are having issues, I know how frustrating they are, especially when intermittent.
After an apologetic takeover of this thread, I and most everyone who helped along the way concluded my issue turned out to be something other than the Sniper.
Here is a lengthy update:
I learned a tremendous amount about the Sniper during this process. Most importantly and in my opinion, all other components need to be in really good working order to optimize it’s performance and diagnose any poor running conditions, in my opinion a sniper doesn’t improve an engine with issues, in fact, I think it may magnify them as I feel it has less margin for error over a really good carb setup on old engine, but far more upside on a healthy one.
Here is brief recap of my efforts. Before replacing the head gasket, I drained the fuel to confirm the tank was clean and replaced all of fuel filters/pump, the valves had just been adjusted along with the nee OEM head and Remflex exhaust gaskets, I put on a brand new Sniper as Holley was perplexed and wanted me to send them the old one for diag, I changed the Dist cap, rotor and module, BUT the one thing I didn’t do in my efforts was to change the DUI distributor itself.
As the dist was removed for switchover there was an odd clicking sound discovered when rotated, not 100% it was the issue, the decision had been made and the motor was out at time, but a sticky/notchy distributor could align with my running condition. Runs good until it doesn’t and something occurs much like it is out of time suddenly and then after varying periods of time of engine off rest, it would correct itself, sometimes run well for minutes, sometimes hours and even a couple of days once. Yes, there are still other possibilities; could have been a valvetrain/piston/ring issue although those are more typically consistent and a decent possibility of a hairline crack in the head itself that caused the initial blown headgasket that began this saga.
We may never know for certain the true cause as I decided to take the nuclear option and just replace the entire drivetrain, engine, trans, TC, etc.
Was that 100% necessary, probably not. I bet many more hours and more money could have been invested to further diagnose and correct to get a few more years out of the old original tiredish 2F. The compression was 120-130, not great but there are lots on the road with that or less, I have read, lowish compression and a Sniper isn’t a great combination, but mine ran fine, till it didn’t.
Also, to help justify the decision for a new Hi Po 2F, I really wanted to do the H55 trans and TC, it just made sense to do it all at the same time.
Wish I could be more help and point to the exact cause, I hope you discover your cause and correction easier than I did.
Sorry to hear you are having issues, I know how frustrating they are, especially when intermittent.
After an apologetic takeover of this thread, I and most everyone who helped along the way concluded my issue turned out to be something other than the Sniper.
Here is a lengthy update:
I learned a tremendous amount about the Sniper during this process. Most importantly and in my opinion, all other components need to be in really good working order to optimize it’s performance and diagnose any poor running conditions, in my opinion a sniper doesn’t improve an engine with issues, in fact, I think it may magnify them as I feel it has less margin for error over a really good carb setup on old engine, but far more upside on a healthy one.
Here is brief recap of my efforts. Before replacing the head gasket, I drained the fuel to confirm the tank was clean and replaced all of fuel filters/pump, the valves had just been adjusted along with the nee OEM head and Remflex exhaust gaskets, I put on a brand new Sniper as Holley was perplexed and wanted me to send them the old one for diag, I changed the Dist cap, rotor and module, BUT the one thing I didn’t do in my efforts was to change the DUI distributor itself.
As the dist was removed for switchover there was an odd clicking sound discovered when rotated, not 100% it was the issue, the decision had been made and the motor was out at time, but a sticky/notchy distributor could align with my running condition. Runs good until it doesn’t and something occurs much like it is out of time suddenly and then after varying periods of time of engine off rest, it would correct itself, sometimes run well for minutes, sometimes hours and even a couple of days once. Yes, there are still other possibilities; could have been a valvetrain/piston/ring issue although those are more typically consistent and a decent possibility of a hairline crack in the head itself that caused the initial blown headgasket that began this saga.
We may never know for certain the true cause as I decided to take the nuclear option and just replace the entire drivetrain, engine, trans, TC, etc.
Was that 100% necessary, probably not. I bet many more hours and more money could have been invested to further diagnose and correct to get a few more years out of the old original tiredish 2F. The compression was 120-130, not great but there are lots on the road with that or less, I have read, lowish compression and a Sniper isn’t a great combination, but mine ran fine, till it didn’t.
Also, to help justify the decision for a new Hi Po 2F, I really wanted to do the H55 trans and TC, it just made sense to do it all at the same time.
Wish I could be more help and point to the exact cause, I hope you discover your cause and correction easier than I did.
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I have worked on all types of cars as an amateur (but semi-pro for side gig) for apparently 40+ years. And there sometimes are intractable problems that are best solved nuclearly! And as Desmocruiser states he ends up “fully restored” on the other side! Regularly on this site you will see those that must give up and sell, I was happy this will have the best ending (and that I’m not paying!)
I get it….I lived with a low compression motor with an Weber for over 8 years. About 2 years ago, I had @Trollhole complete an ‘intentionally full motor rebuild - I provided them the replacement long block so I could enjoy the 40 until the motor was ready. Even with their connections, they had supply chain issues - but came through with a finished build that I AM very happy with - despite some trail-side issues. When you have a 50 treat old truck - you never know what component or connection is gonna come loose and give you an issue. While they had it, I had them add Vintage Air AC, ARB rear locker, w/pump and custom wired & plumbed my aux tank - along with a Sniper EFI, an unplanned for Saginaw (because my original PS was no longer compatible with later block) power steering, etc, etc. I eventually found a local (to me) hot rod shop with an owner that was VERY familiar with the Sniper. He retuned it twice after getting it back, and the Sniper had been reliable - until I TRIED to resolve a trailside coil failure… and I needed backups to help me get back running again - which it is.
I am certain Nolen and team will get you taken care of….
I am certain Nolen and team will get you taken care of….
Don’t feeltoo bad though…not an uncommon way to solve a problem. While mine is much less cost than @desmocruiser …. It is the same concept. My original Weber carb ran ok, it always coughed a little on start and once in a while when you step on the accelerator full tilt! I had the Sniper in the box in the garage for almost 16 months before installing it. The sniper ran really well. Never had issues and to make a long story short.. and $3900 later I loved the sniper so much I added the Mosley modified Holley Hyperspark ignition. It ran even better and utilized that blank TIMING display on the EFI handheld
Reality is…with just the Weber…all I needed to do was advance the timing on the DUI distributor 3* or so !!! . I love my combo now.it starts instantly summer and winter…instantly!
Reality is…with just the Weber…all I needed to do was advance the timing on the DUI distributor 3* or so !!! . I love my combo now.it starts instantly summer and winter…instantly!
Back in April I got a PM from @desmocruiser
Seems reasonable right? I know this guy. He drives a HZJ73 I built a while back. He gave me really good beers at the 70 ride at Windrock. Why not.
Seems reasonable right? I know this guy. He drives a HZJ73 I built a while back. He gave me really good beers at the 70 ride at Windrock. Why not.
It appears that the thread got hijacked.
How did your Holley Sniper 2GC come out? Did you use the large bore or the small bore?
I like the 2GC since it appears to look a bit more factory than the standard sniper that everyone is using. It looks like it will mate up well with the factory air box without that big clunky adapter that is needed for the standard sniper. Can you confirm?
They stopped making the 2GC big bore. Not sure on the small.
All of the Holley 2 Barrels are currently marked “back ordered” on their website (just FYI). The 2300 seems popular in general (as much CFM as even most V8 motors can take) so I assume it will get restocked. Or it gets updated to Sniper 2!
Summit has 2300s. The 2GC thing happened about 18 months ago. Made Mosley have to redo a lot. All
Of his 3F and 1FZ work was based on the 2GC and the adapters he made
Of his 3F and 1FZ work was based on the 2GC and the adapters he made
Is the 2GC a viable option? I understand that everyone is partial to the 2300 sniper and probably best since there are so many threads on the topic. But as stated previously, it looks though it look almost OEM. Again, I am not to partial of the adapter to air box.
I thought you did a thread on this. I couldn’t find it.
Not anymore. Discontinued