Holley Sniper 2 barrel conversion

[BrianSanDiego]

Thanks for the info. I’ve got a pressure gauge coming that I’ll plumb in just for piece of mind. Can’t wait to get up and running!

The fuel gauge is very helpful in troubleshooting fuel supply problems obviously, but also very helpful in diagnosing fuel pressure regulator or return line issues, which the Sniper is prone to. They oversize the fuel pump, and the FPR and return line need to return a LOT of fuel to the tank, without obstruction. If your return line isn't sufficient you'll have high fuel pressure, but the gauge will tell you that at-a-glance.
I think a pressure gauge is almost a necessity on these things.

 

[wngrog]

The one time I got some bad gas and clogged my fuel filters the Sniper told me my Duty Cycle was pegged.

I use a PowerSurge and therefore I can still use a low pressure clear OEM fuel filter.

I cracked the hood and sure enough it had garbage all in it.

Changed it and the high pressure filter downstream and it went back to running great.

 

[NOSAJ]

Thinking about doing this on my ‘77. What kind of mpg are y’all seeing?

 

[wngrog]

Thinking about doing this on my ‘77. What kind of mpg are y’all seeing?

Don’t do this for the MPG.

 

[NOSAJ]

Thanks @wngrog. I guess I’ll stick to my diesel plan!

 

[wngrog]

Thanks @wngrog. I guess I’ll stick to my diesel plan!

yeah I just bought a 55 gallon tank to offset the low double and high singles I get in my pig

 

[Fj moneypit]

Made it out of the garage after the sniper 2300 efi install. Had a couple stalls and a couple hiccups but man it runs much nicer and more throttle response than the carb. I’m assuming it’ll take a little more learning for it to be smooth. I’ll reassess everything and start to daily drive it.

 

[Dizzy]

Made it out of the garage after the sniper 2300 efi install. Had a couple stalls and a couple hiccups but man it runs much nicer and more throttle response than the carb. I’m assuming it’ll take a little more learning for it to be smooth. I’ll reassess everything and start to daily drive it. View attachment 2178569

Which carb? '75 Aisan Federal?

 

[Fj moneypit]

Which carb? '75 Aisan Federal?

Aisan early 75

 

[Fj moneypit]

Question for all those who have done the efi. So I’ve had limited driving time so far but seems like the efi has learned now not to stall when coming to a light. Had some issues when going up an on-ramp to freeway. Ramp was slight upgrade. The efi coughed and backfired a couple time. Is this just another computer leaning process? Anyone else have these or other things that ironed themselves out?

 

[wngrog]

Question for all those who have done the efi. So I’ve had limited driving time so far but seems like the efi has learned now not to stall when coming to a light. Had some issues when going up an on-ramp to freeway. Ramp was slight upgrade. The efi coughed and backfired a couple time. Is this just another computer leaning process? Anyone else have these or other things that ironed themselves out?

I always ask people to make sure the Idle Air Contol and Throttle Position sensor are set correctly per the manual.
If so, then check your duty cycle when it’s doing that. Is it high? Could possibly be a clogged fuel filter.

 

[Fj moneypit]

I always ask people to make sure the Idle Air Contol and Throttle Position sensor are set correctly per the manual.
If so, then check your duty cycle when it’s doing that. Is it high? Could possibly be a clogged fuel filter.

should be set right but I’m going to go thru manual. It’s running pretty darn good today though.

 

[Jdc1]

In searching for material for the stock F air cleaner to sniper adaptor, I stumbled across these aluminum spacers;

Allstar Performance ALL25947 Allstar Performance Air Filter Spacers | Summit Racing

Free Shipping - Allstar Performance Air Filter Spacers with qualifying orders of $109. Shop Air Filter Assembly Spacers at Summit Racing.

www.summitracing.com

They are 5 1/8” diameter and come in different heights. I am using the Redline adaptor and it sits pretty high.

 

[Steamer]

I got the 2" high "Allstar spacer" and can say it's machined very well and is a good fit on top of the Sniper. My stock air filter stuff is long gone and I just use generic stuff so I can't speak for the top end of it fitting anything. I haven't found a generic filter to fit on top of the spacer so it's set aside for now till I fab up something. I'm looking to move my generic filter higher so I have more room to modify my hand throttle linkage.

 

[Jdc1]

I got the 2" high "Allstar spacer" and can say it's machined very well and is a good fit on top of the Sniper. My stock air filter stuff is long gone and I just use generic stuff so I can't speak for the top end of it fitting anything. I haven't found a generic filter to fit on top of the spacer so it's set aside for now till I fab up something. I'm looking to move my generic filter higher so I have more room to modify my hand throttle linkage.

I am going to close the top side and weld in a 3” tube to mate to the stock air cleaner.

 

[thecrazygreek]

I have been working on a 3D printed adapter for my set up which is a bit different than yours, but if you could give me dimensions I could give it a shot. Printed in high temp abs so no warping issues in normal conditions.
would need exact measurements. And offset from sniper to air leaner.
I imagine it would end up looking similar to redlines, or perhaps the other style that slopes.
let me know if you’re interested.

 

[Fj moneypit]

I built mine form the adapter kit. I thought a print would be the way to go. Be nice to have made out of hard plastic

I have been working on a 3D printed adapter for my set up which is a bit different than yours, but if you could give me dimensions I could give it a shot. Printed in high temp abs so no warping issues in normal conditions.
would need exact measurements. And offset from sniper to air leaner.
I imagine it would end up looking similar to redlines, or perhaps the other style that slopes.
let me know if you’re interested.

 

[Fj moneypit]

So some questions for those who have it dialed in. I’ve had a problem getting the iac set. I’ve set it at operating temp to about 4. Drove a while and no problem. Later iac was at 1. Also my tps may be causing some problem or possible stall in relation to the iac. My tps reads 0. Every once in a while it’ll get stuck at 1%. I’ve been able to fix by tapping gas. My throttle may not getting full return. Anyone have a good linkage setup? I wonder if all problems can be related to the linkage. Any other values to look at to dial this in. What are your settings?

 

[wngrog]

All those numbers are well within spec.

What RPM is your idle?

Where is your timing?

 

[Fj moneypit]

All those numbers are well within spec.

What RPM is your idle?

Where is your timing?

rpm is set for 650. Usually sits about 650-670. Timing 10* at flywheel. 15* at idle per Holley specs on the ecu.