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Thread: Sniper & dual sync tuning tips.

  1. #1

    Default Sniper & dual sync tuning tips.

    Hello all. I'm looking for some pointers on a couple minor issues I seem to be having. I have a fresh install with around 300 miles so far. Engine is a new long block l-31R from Chevrolet aka Vortec 350. I have a Weiand Street Warrior dual-plane intake, Hedman Black Maxx 1-5/8" 14 gauge primary long tube headers, 2.5" dual exhaust with H-pipe just behind cab, Borla ProXS mufflers, WBO2 sensor ~5" after collector, 3/4 phenolic spacer, Holley Sniper, dual sync distributor, new fuel baffled fuel tank with EP381 pump in tank, 3/8" supply & return, TH400 trans, Hughes XTM low stall torque converter in a K30 with 3.73s & 33" tires. Not sure all that is relevant, but I wanted to be thorough. I have target idle set to 750 in neutral, which puts it around 650 in gear. Base timing set to 15° WOT 32° part throttle cruise 36°

    Here are my observations. Some may be relevant some may not be:
    Engine starts fine most of the time. only on a couple occasions has it required me to crank it over a second time, but usually fires right up. Do I need to change fuel prime settings?

    Sometimes when I leave in the morning, I accidentally push the stiff throttle a little too much and spin the tires momentarily in my gravel driveway. When I ease out of it, RPM can dip quite low for a brief moment. This has resulted in the engine stalling, but only once or twice; it usually recovers. only seems to happen when I apply the throttle as gently as possible then get back out of it.

    Once, under hard braking, the truck stalled.

    If I blip the throttle from zero to full throttle in my driveway in park, it'll choke out. Almost like a non pumper carb would do. It'll sometimes bog off the line in gear. Holley tech support told me to bump the acceleration enrichment up 5 lbs at a time until the problem is resolved. I started around 50 (factory default) and I'm now up to 75. Kind of odd that whatever value I set, after hitting save it saves at a value .2-.3 lower than what I selected. I.E. if I select 75, it'll save at 74.8. Should I keep going up?

    My IAC value is always 30% when cruising.

    When attempting to customize multi-gauge layout, by the time I get to assigning my second value (which for my personal situation is CTS) the handheld will freeze and display four Js as if they are buttons that can be pressed, but it's locked up. Only cycling the ignition to reboot handheld will fix this issue. I believe my firmware is fine, because it displays Sniper on the screen and not Holley or whatever the old firmware did for some. I spoke to Holley tech support and they walked me through resetting my firmware, but the tech didn't seem super knowledgeable. After I got off the phone, I turned the ignition on and knew something was not right because my fuel pump would prime like it had before. My only fix for this was re-running the Wizard, effectively resetting the unit.

    Other than those described issues, it seems to be doing its thing. Is the Sniper in Learn mode by default after initial startup? Thank you very much in advance for your help!

  2. #2

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    All of the answers to your questions are inside of your Sniper, but you'll need to learn how to run and view datalogs to see the answers. Once you know how to run and view a datalog the Sniper will be your best friend. You can then make adjustments to the tune and see the results. You don't need a laptop to do this, you just need to run a datalog and then put the SD card in your desktop computer and use the Holley SW to view it.

  3. #3
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,412

    Default

    Quote Originally Posted by jpgreenwood View Post
    Is the Sniper in Learn mode by default after initial startup?
    The Sniper EFI only enters Learn mode at 160°F. It enters Closed Loop mode as soon as the WBO2 sensor completes its initial heating cycle.
    Check your Closed Loop/Learn parameters. "Enable Closed Loop" and "Base Fuel Learn Enabled" are the only parameters that need to be check marked.

    Closed Loop & Learning happens at all RPM, provided the Closed Loop/Learn Parameters are programmed as such.
    The Coolant Temperature Enrichment % & A/F Ratio Offset tables must be at 100% & zero to enter Learn mode.
    You'll need to reconfigure these tables if you're running the engine colder than what the base calibration specifies.

    It's disappointing to read a question like this, because it means you haven't read the Sniper EFI manual:
    http://documents.holley.com/techlibrary_199r11259.pdf (Holley Sniper EFI Help Manual - EFI Software, Tuning & Datalogging)
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: Dominator MPFI & DIS, A/C, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/X-pipe/shorty headers, 100HP progressive dry direct-port NOS, 160A 3G alternator, Optima Red battery, LenTech Strip Terminator wide-ratio AOD/2500 RPM converter, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

  4. #4

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    I don’t have a laptop or desktop. I only have a smartphone and in my rural area data service is spotty at best. I do my best to learn what I can when in a town with cell coverage. I'll purchase a computer soon, thanks.

    My Sniper didn’t come with a manual. Only a Quick Start Guide and installation paperwork. I didn’t know there was anything outside of the provided materials, Holley tech and this forum. I’ll download the link, thanks.

  5. #5
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
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    Here's another good informative Sniper EFI forum post: https://forums.holley.com/showthread...2178#post92178 (Sniper EFI Troubleshooting & Technical Information)
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: Dominator MPFI & DIS, A/C, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/X-pipe/shorty headers, 100HP progressive dry direct-port NOS, 160A 3G alternator, Optima Red battery, LenTech Strip Terminator wide-ratio AOD/2500 RPM converter, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

  6. #6

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    OK, I guess I’ll head to Costco to pick up a computer. I was under the impression that you install the sniper and it tunes itself. This might as well all be in Cantonese to me, LOL! First section of the user manual and I’m already lost. It says “Downloading a Base Config File”. Downloading from where? To what? Sorry for all the stupid questions. Your talking to a guy who just got a smart phone not that long ago. I used computers in college, but only for writing papers on Kinesiology or Organic Chemistry and haven’t had one since. I go to friend’s houses or the library, but that’s not going to cut it, I guess. I’m assuming I pull the chip out of the handheld and put it in the computer, don’t really know what I’m doing from there. Will any computer work? I.E. Apple, Windows. Thanks for your patience.

  7. #7

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    Well the good news is that the Sniper does tune itself. The bad news is that it assumes you have a SB Chevy engine and that you live at sea level and a few other things like that. So some of the tables have generic values in them which may or may not work for you. Those tables do not "Learn" so what you get is what you'll have forever unless you modify them. I have a 500 inch big block in my car and the stock tables would not allow it enough air to start when hot. I had to plug a laptop into my Sniper to change the IAC park position and now it starts just fine when hot. If I didn't plug a laptop in and tune that table the Sniper would not have ever learned how to do it and my car would not have ever started when hot.

    So yeah, you kind of need access to a Windows computer (desktop or laptop) in order to really tune a Sniper. If you are going to buy a new computer just for the Sniper you don't need to buy anything really expensive. I use a laptop that I bought for $300 at Costco for my EFI tuning. All you really need is Windows 10, a couple of USB ports and a SD card slot. Built-in WiFi or ethernet so you can get on the internet and you should be good to go. If you don't have good internet access then you'll be a little screwed since all of the information is on the Holley website. You might need to got the public library and spend a few hours reading instructions on the Holley website and/or printing them out.

  8. #8

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    I really really don’t mean this to come across harshly, but if you truly have no computer and very limited computer skills, a carb might be a much better idea for your engine. It will be significantly simpler to use. Are you experienced with engine tuning? How about wiring?

  9. #9
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    21,412

    Default

    Quote Originally Posted by jpgreenwood View Post
    I’m assuming I pull the chip out of the handheld and put it in the computer, don’t really know what I’m doing from there.
    https://forums.holley.com/showthread...8883#post98883 (Holley Sniper EFI Save Config File On SD Card, LINK - Page 73)

    Will any computer work? I.E. Apple, Windows. Thanks for your patience.
    Stop what you're doing (before your engine suffers damage) and get yourself properly equipped with a computer (laptop or PC). The Sniper EFI software is a Windows based program.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: Dominator MPFI & DIS, A/C, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/X-pipe/shorty headers, 100HP progressive dry direct-port NOS, 160A 3G alternator, Optima Red battery, LenTech Strip Terminator wide-ratio AOD/2500 RPM converter, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

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