[Old Buzzard]

We put the Sniper on a BBC. The first set of injs lasted long enough to run the Power Tour. Then 1 inj died. Holley replaced it. Second one died. I have an inj flow bench, so I ran all 4. 3 worked, one was a dead player.
Sent the unit back to Holley. They sent a new unit. N/C.

 

[whopay]

My O2 sensor is on the right side about 6 inches below the junction of the manifold

 

[hutchenc]

We put the Sniper on a BBC. The first set of injs lasted long enough to run the Power Tour. Then 1 inj died. Holley replaced it. Second one died. I have an inj flow bench, so I ran all 4. 3 worked, one was a dead player.
Sent the unit back to Holley. They sent a new unit. N/C.

Damn...that is not a ringing endorsement. The Sniper units seem to have a lot of problems.

 

[Old Buzzard]

I've also

Damn...that is not a ringing endorsement. The Sniper units seem to have a lot of problems.

worked/installed the MSD and the Fitech units.
No problems w/ the MSD. [Now owned by Holley.]
The Fitech has/had bad tech support.
Currently we have a FAST unit, on a BBC. It's been sitting for 5 yrs, and never started. That should be a "hoot", getting it to work.:dontknow:

 

[55 Tony]

My O2 sensor is on the right side about 6 inches below the junction of the manifold

I'm curious if the location of the o2 sensor and dual exhaust can be a problem with some installations. Do any factory units have the sensor on just one side? (obviously I'm not up on newer car systems with dual exhaust).

Might be a good diagnostic tool to install a bung in the other side and plug that hole? I did that with my A/F gauge just to be sure both sides are equal.

 

[Rick_L]

Tony, if you've had the A/F sensor in both sides you know the answer. Most of those units use the same wide band sensor that's used with aftermarket EFI, and only one of them. The other bank is going to be the same unless something is wrong. And EFI is more likely to be the same bank to bank than a carb.

OEM EFI setups use a second sensor on V6 and V8 applications because of a "belt and suspenders" approach for emissions.

 

[rayharris]

My O2 sensor is on the right side about 6 inches below the junction of the manifold

That should be good.
Don`t know about this site,but it is very informational. https://www.efisystempro.com/?utm_s...6800&goal=0_9220bdb74c-e418f24a6b-161926800&mc_cid=e418f24a6b&mc_eid=a8d1aa59b5 :anim_25:bowtie-trifive:gba:

 

[rayharris]

I have one installed in my 55 truck. 327 mostly stock except for being 30 over.
When I installed mine, I located the o2 sensor about 14 inches from my collectors. The recommended location is no more than 9 inches. The system would not operate correctly. It back fired and did all sorts of funny things. I called Holley, they said check the fuel pressure and the o2 sensor. My fuel pressure was 55 psi. I relocated the o2 sensor and it changed everything. There is one thing I do not like about this system and that is the fuel pump is noisy. I can here it run while driving. :anim_25:bowtie-trifive:gba:

 

[hotrodg726]

I'm curious if the location of the o2 sensor and dual exhaust can be a problem with some installations. Do any factory units have the sensor on just one side? (obviously I'm not up on newer car systems with dual exhaust).

Might be a good diagnostic tool to install a bung in the other side and plug that hole? I did that with my A/F gauge just to be sure both sides are equal.

most gm obd1 systems had a single non heated O2 sensor (tpi tbi)

 

[whopay]

There is one thing I do not like about this system and that is the fuel pump is noisy. I can here it run while driving. :anim_25:bowtie-trifive:gba:

A work around for that is use the Tanks Inc (or similar) set up of an internal fuel pump in a fuel injection baffled fuel tank. I set mine up this way and that part of it I am happy with. It added some to the expense but none of the noise you are talking about. I think this is the only way I would set it up.

 

[Old Buzzard]

I have one installed in my 55 truck. 327 mostly stock except for being 30 over.
When I installed mine, I located the o2 sensor about 14 inches from my collectors. The recommended location is no more than 9 inches. The system would not operate correctly. It back fired and did all sorts of funny things. I called Holley, they said check the fuel pressure and the o2 sensor. My fuel pressure was 55 psi. I relocated the o2 sensor and it changed everything. There is one thing I do not like about this system and that is the fuel pump is noisy. I can here it run while driving. :anim_25:bowtie-trifive:gba:

Did you take the exh pipe off, to relocate the bung?

 

[55 Tony]

Did you take the exh pipe off, to relocate the bung?

I don't have FI but I put my a/f sensor bungs on the collectors because I could pull them off easy to weld.

Also be sure your sensors are on the top half of the pipe. On start up the water that condenses inside the cold pipe and doesn't have a chance to evaporate can get into the sensor and screw it up permanently.

 

[Old Buzzard]

We do that..

I'm curious if the location of the o2 sensor and dual exhaust can be a problem with some installations. Do any factory units have the sensor on just one side? (obviously I'm not up on newer car systems with dual exhaust).

Might be a good diagnostic tool to install a bung in the other side and plug that hole? I did that with my A/F gauge just to be sure both sides are equal.

if the exh is a new install. I do that on my personal cars, too.
My EFI LIVE tune tool is set up to "spoof" the narrow band sensor, that I take out, to put the WB in. ECM still sees a NB signal, and I see the WB.
I/we don't use the clamp on adapters. Too much chance for a leak.
My LS install, in the rust bucket, has 2 bungs, on each side. [The LS uses 2 heated NB sensors].
MOST frequent issue doing tuning/troubleshooting is, exh leaks. It WILL give you fits!:banghead:
Cheapo headers, poor connections, blown gaskets, are the most frequent we find.

 

[rayharris]

A work around for that is use the Tanks Inc (or similar) set up of an internal fuel pump in a fuel injection baffled fuel tank. I set mine up this way and that part of it I am happy with. It added some to the expense but none of the noise you are talking about. I think this is the only way I would set it up.

Problem is, they don`t make the tank for the truck.bowtie-trifive:gba:

 

[rayharris]

Did you take the exh pipe off, to relocate the bung?

No, I cut a new hole with a cutting torch. Welded up the old bung hole. bowtie-trifive:gba:

 

[whopay]

Well I am dusting off my account and realized I left my problem with the Sniper unanswered. I finally found the issue! It has been running AMAZING for the last two years. I plan to drive it from lower AL to the Nationals this year.

problem? You will never guess.

 

[whopay]

I have my battery in the trunk and the power for the car first connects at the starter solenoid. This is where I connected the Sniper for its power. It worked great for several years because I was only taking small drives. Once I started taking longer drives the heat caused the “dirty” power to act up. Wired direct to battery (per current instruction manual) and it has been great.

all the other stuff I did helps make it all the more smooth.Been very happy.

 

[Alloy]

I have my battery in the trunk and the power for the car first connects at the starter solenoid. This is where I connected the Sniper for its power. It worked great for several years because I was only taking small drives. Once I started taking longer drives the heat caused the “dirty” power to act up. Wired direct to battery (per current instruction manual) and it has been great.

all the other stuff I did helps make it all the more smooth.Been very happy.

So did you move the battery back to the engine compartment?

I have my battery in the trunk and I'm working on installing a sniper injection at we speak.'

 

[whopay]

[Edited!] No, I kept it in the trunk but save yourself some trouble and have a dedicated ground and power for the sniper direct to the battery.

 

[whopay]

I simply could not believe that was the issue on mine but without a doubt the dirty power (and maybe the ground too) gave the sniper a hard time.