Holly sniper EFI

2373 Views 19 Replies 5 Participants Last post by GriffinB, Nov 25, 2021

Fighting wolf

Discussion Starter · Nov 20, 2021

Hey y'all have a question. I have an 85 bronco 351w with Holly sniper and tuning her. For everyone that has one what is everyone running for the afr target and ignition timing spark for idle cruise and wot

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Doosenberry

· #2 · Nov 20, 2021

Might vary a bit depending on the engine type and how "built" it is, but I'll share my settings. Mine is on a 10:1 compression 460 with iron heads that made 450hp @ 5k rpm on the dyno, for reference.

12.5:1 @ WOT
13.5:1 @ idle
14.9:1 @ cruise

My initial ignition timing is set @ 15 degrees.
Max timing is set @ 34 degrees.

I haven't manually tuned the curve on either the AFR or the ignition timing other than using the settings on the handheld. I don't currently have a computer to tune with, but the settings I have seem to be doing ok. I'd like to adjust the timing curve the most as it's a very short, very steep curve going from 15 to 34. Something like 1500-2500 rpm it goes from 15-34 degrees.

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Fighting wolf

Discussion Starter · #3 · Nov 20, 2021

Just a 351w with a slight cam and long tube headers. Is that for afr or spark timing

Hillbilly Heaven

· #4 · Nov 20, 2021

Unless you are really placing a heavy load like lugging it above 3000, bringing in the full advance by 2500 is the correct thing to do. Look at your cruise rpm and it should be close to full advance by then. If you lug the engine above 2500 with full advance or lug it below 2500 with a high initial timing this is where you get pre ignition.

Typically on an iron head motor 12-15 initial and 32 to 36 max and all in by 3000. Aluminum head motor you get by with a little more timing.

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Jimmy Dean

· #5 · Nov 24, 2021

I am at 10 degrees on my mild build 86 351W w/ holley sniper and full hyperspark ignition. I have full set at 35 at 2500 RPMs. aluminum heads/intake, 9.1:1 compression, car cam (high RPM cam)

I have ZERO miles on it so far, but about 2 hours of run time. I am waiting on power steering parts at the moment to get her onto the road and check everything.

Jimmy Dean

· #6 · Nov 24, 2021

oh, AFRs.

14.0 idle, 14.3 cruise. 12.5 WOT is the goal. Ill have to play with those some.

Reactions: 1

Fighting wolf

Discussion Starter · #7 · Nov 24, 2021

Jimmy Dean said:
oh, AFRs.

14.0 idle, 14.3 cruise. 12.5 WOT is the goal. Ill have to play with those some.

Thank you I'll give that a try and see what she does

Fighting wolf

Discussion Starter · #8 · Nov 24, 2021

Doosenberry said:
Might vary a bit depending on the engine type and how "built" it is, but I'll share my settings. Mine is on a 10:1 compression 460 with iron heads that made 450hp @ 5k rpm on the dyno, for reference.

12.5:1 @ WOT
13.5:1 @ idle
14.9:1 @ cruise

My initial ignition timing is set @ 15 degrees.
Max timing is set @ 34 degrees.

I haven't manually tuned the curve on either the AFR or the ignition timing other than using the settings on the handheld. I don't currently have a computer to tune with, but the settings I have seem to be doing ok. I'd like to adjust the timing curve the most as it's a very short, very steep curve going from 15 to 34. Something like 1500-2500 rpm it goes from 15-34 degrees.

Awesome I'll give that a try and see how she reacts

Jimmy Dean

· #9 · Nov 24, 2021

Fighting wolf said:
Awesome I'll give that a try and see how she reacts

I do suggest playing with the fuel cutoff on decel if you want to get rid of the popping if yours is doing it. mine does. as this is a DD, I do not care for that much.

Fighting wolf

Discussion Starter · #10 · Nov 24, 2021

Jimmy Dean said:
I do suggest playing with the fuel cutoff on decel if you want to get rid of the popping if yours is doing it. mine does. as this is a DD, I do not care for that much.

She doesn't get ran much. I use her mainly for plowing snow in the mountains. Once I get the tune good and running better I might take her to town every now and then

Jimmy Dean

· #11 · Nov 24, 2021

Fighting wolf said:
She doesn't get ran much. I use her mainly for plowing snow in the mountains. Once I get the tune good and running better I might take her to town every now and then

gotcha, I rely on mine for my DD, and now that my boy is in scouting, we'll be taking her on more trips as well, so I am hopign the sniper is as reliable as being carbed was, but with better gas mileage and performance in the hills with a load. 8mpg daily sucks.

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Fighting wolf

Discussion Starter · #12 · Nov 24, 2021

Jimmy Dean said:
gotcha, I rely on mine for my DD, and now that my boy is in scouting, we'll be taking her on more trips as well, so I am hopign the sniper is as reliable as being carbed was, but with better gas mileage and performance in the hills with a load. 8mpg daily sucks.

Definitely agree haha.

Jimmy Dean

· #13 · Nov 24, 2021

Fighting wolf said:
Definitely agree haha.

how long have you been running with the sniper? Any EMI/RFI issues? randomly shutting down? s tock ignition or aftermarket?

I ask, because I did the swap last year, and had to go back to carb, she was randombly cutting off due to EMI issues tripping the ECU. This year while I had the engine apart for a burnt valve I upgraded to hyperspark dizzy, coil, and box. have only had 1-2 EMI issues so far, but nothing on the graphs indication what the issue is. I really need this to not randomly cut out, even if that is only once in a hundred miles or something, because this thing sees a few hundred miles a week on commuting and normal day to day stuff, and then at least once a month a few hundred mile trip for camping and back.

Fighting wolf

Discussion Starter · #14 · Nov 24, 2021

Jimmy Dean said:
how long have you been running with the sniper? Any EMI/RFI issues? randomly shutting down? s tock ignition or aftermarket?

I ask, because I did the swap last year, and had to go back to carb, she was randombly cutting off due to EMI issues tripping the ECU. This year while I had the engine apart for a burnt valve I upgraded to hyperspark dizzy, coil, and box. have only had 1-2 EMI issues so far, but nothing on the graphs indication what the issue is. I really need this to not randomly cut out, even if that is only once in a hundred miles or something, because this thing sees a few hundred miles a week on commuting and normal day to day stuff, and then at least once a month a few hundred mile trip for camping and back.

I haven't had any of those issues. I installed everything for the sniper. ignition, distributor everything only issue I've had is getting it properly tuned I don't hard drive enough for it to program so have to manually do it

Jimmy Dean

· #15 · Nov 24, 2021

Fighting wolf said:
I haven't had any of those issues. I installed everything for the sniper. ignition, distributor everything only issue I've had is getting it properly tuned I don't hard drive enough for it to program so have to manually do it

can you post a picture of your install? box and coil locations, wire routing, what you did with the excess wire harness, etc?

Fighting wolf

Discussion Starter · #16 · Nov 24, 2021

Jimmy Dean said:
can you post a picture of your install? box and coil locations, wire routing, what you did with the excess wire harness, etc?

I put the coil on the passenger side fender wall it's sitting on a temporary bracket till I can make a better due to the length of the coil wire to the distributor being too short and put the box under the heater box in the cab and just wound up the access wires with a zip tie under the dash

Jimmy Dean

· #17 · Nov 24, 2021

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Fighting wolf said:
I put the coil on the passenger side fender wall it's sitting on a temporary bracket till I can make a better due to the length of the coil wire to the distributor being too short and put the box under the heater box in the cab and just wound up the access wires with a zip tie under the dash

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my setup, this was before I had everything completed, everything is together and running now. I will need to make a custom set of wires, these are just too short and pulled too tight in places, which is annoying for how much they set me back.

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GriffinB

· #18 · Nov 25, 2021

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This is how I have mine setup and the biggest issue I have is with the IAC surging randomly causing a high idle. I also love the pops on deceleration but I’m also 18 and it’s not my DD anymore. Got a crown Vic that gets 21 compared to 8. Once I fix the engine I plan on taking it to a Holley sniper certified shop to see if they can figure it out if I can’t. Which so far I haven’t been able to.

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Jimmy Dean

· #19 · Nov 25, 2021

GriffinB said:
This is how I have mine setup and the biggest issue I have is with the IAC surging randomly causing a high idle. I also love the pops on deceleration but I’m also 18 and it’s not my DD anymore. Got a crown Vic that gets 21 compared to 8. Once I fix the engine I plan on taking it to a Holley sniper certified shop to see if they can figure it out if I can’t. Which so far I haven’t been able to.

ok, not havcing issues is good. mine is setup almost the same as yours, minus I didn't cut out all the extra wire. I'll do that next if I still have issues once I start driving it. I've worked hard to minimize the amount of wires headed to the engine, clean up the clutter so to speak. whenever I pull the motor next, I'll be doing much more in that regards to the entire engine bay. make it look clean.

GriffinB

· #20 · Nov 25, 2021

Jimmy Dean said:
ok, not havcing issues is good. mine is setup almost the same as yours, minus I didn't cut out all the extra wire. I'll do that next if I still have issues once I start driving it. I've worked hard to minimize the amount of wires headed to the engine, clean up the clutter so to speak. whenever I pull the motor next, I'll be doing much more in that regards to the entire engine bay. make it look clean.

I also should do that and clean up the mess of factory wiring on the driver side fender liner that’s been there since I restored it. I plan on taking it out December and figuring out what’s making my engine smoke a lot and sound very clanky. Possibly a full rebuild but I hopefully no machine shop work. Also plan on getting rid of the AOD for a zf5 and selling the AOD while it works.

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