Results 1 to 9 of 9

Thread: Super Sniper surging - Files attached, Please help.

  1. #1

    Default Super Sniper surging - Files attached, Please help.

    Friends. The engine, stroked 351 Cleveland to 381. 10:3, .625 life, .235 duration to give context on cam.
    Single-plane Torker style intake, Motor dynoed 508 HP with a carb before the Sniper. I have the 8 injector super sniper and HyperSpark distributor. Sniper is controlling timing.

    Attached is a video of display, the current config file, and a datalog showing issue. The engine only has 500 miles and on it and has been working flawless until the last two weeks. It's surging high low very bad all of a sudden. I haven't touched any fuel or timing tables. It has been in Learning mode and doing great. Whats going on here? I'm going crazy. I was LOVING this setup. UGGGGG, it's not letting me upload docs.
    Attached Files Attached Files

  2. #2

    Default

    I got the files open fine. I noticed your CL Comp is up and down. For some reason it's adding and then subtracting fuel based off your AFR.

    I see what I suspected. Right at your surging RPM is the transition from 18.5° to 24.5° and then 24.5° to 29.5° on your timing table. I would go in and smooth this transition and see how it does.

    Additionally, your Learn Table is well populated. I would recommend Transfer Learning To Base, smooth out your Base Fuel Table and then see how it reacts. I'll to continue to look it over and see if there is anything else I am missing.
    Last edited by thecowwatcher; 01-25-2020 at 07:40 PM.

  3. #3

    Default

    Any addional thoughts? How do I transfer the Learning to base tables. Seems like the Sniper should do that automatically.

  4. #4

    Default

    The Learn Table is just the Sniper showing what adjustments were made at certain RPM and pressures. It automatically makes the adjustments, but I'd smooth your Timing Table transition first before any further changes. The Sniper may readjust those areas that's surging once the Timing Table is smooth.

  5. #5

    Default

    Okay, I’ll research and read up on how to do the smoothing in that specific RPM range, 1800-3000 RPM.

  6. #6
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    24,063

    Default

    Read the 4th & 5th paragraphs: http://forums.holley.com/showthread....2523#post62523 (Holley EFI Tuning Tips & Information)
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 232°-244° duration/.623" lift/114° LSA camshaft, 11.8:1 comp, TFS R-Series FTI ported intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 200A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/3000 RPM converter, FPP aluminum driveshaft, FPP 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 MT tires.

  7. #7

    Default

    If you're controlling timing, you're running right on the cliff of a big change, if you look at the ignition timing it's mirroring your AFR. You may want to flatten this out and see if it helps.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Timing curve.jpg 
Views:	15 
Size:	96.2 KB 
ID:	9183  
    Last edited by silver74vette; 02-09-2020 at 10:31 AM.

  8. #8
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    24,063

    Default

    Originally Posted by Danny Cabral
    The Target Air/Fuel Ratio Table & Base Fuel/Timing Table (and MAP kPa & RPM axes/scales) should be configured using the Sniper EFI software:
    In the Sniper EFI software (LINK), Target Air/Fuel Ratio Table (Fuel ICF) & Base Timing Table (Spark ICF), select "2D Table" Type (not "Simple").
    The Target Air/Fuel Ratio Table & Base Timing Table can then be properly configured & tuned for any engine.
    https://www.holley.com/support/resou...Fuel_Injection (Sniper EFI Software & Holley 558-443 CAN/USB Dongle)
    https://forums.holley.com/showthread...679#post100679 (Sniper EFI Optional Comm/Data Cable Accessories)
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 232°-244° duration/.623" lift/114° LSA camshaft, 11.8:1 comp, TFS R-Series FTI ported intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 200A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/3000 RPM converter, FPP aluminum driveshaft, FPP 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 MT tires.

  9. #9

    Default

    You wouldn't need the 8 injector Sniper on that engine. Not sure if that's part of the problem or not, but you'll want to keep that possibility in the back of your head. An engine like that only needs the standard Sniper, you wouldn't even need the XFlow version for 585 HP.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
About us
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors have powered every NASCAR® Sprint® Cup team and nearly every NHRA® Pro–Stock champion for four decades. Now, Holley EFI is dominating the performance world as well as our products for GM's LS engine. Holley's products also include performance fuel pumps, intake manifolds & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies - Hooker Headers, Flowtech Headers, NOS Nitrous, Weiand, Earl's Performance Plumbing, or Diablosport - Holley products can give you the edge you need over the competition.
Join us