0° Timing under load, heavy acceleration.

[Teambrauss]

Sniper EFI, Dual Sync distributor, HyperSpark coil, HyperSpark box. 383ci SBC, manual transmission.
The timing goes to 0° upon heavy acceleration or WOT acceleration. 10° at idle. 20ish° with average driving. I've checked settings, currently requesting 40° during WOT. I've spent some time looking for a thread regarding this. I'm sure that I've made a mistake in setup.

[a b c]

Have you looked at the Base Timing Table? Attach the (zip the files first) GCF and a datalog of the event here using the Advanced function at the bottom of reply window and we'll take a look.

[AndyF]

How do you know the timing goes to zero? Are you checking it with a timing light or looking at a data datalog or what? If you have a datalog showing the timing going to zero have you overlaid that on the Base Timing Table in the Config File to see if that's correct or not? The first rule for solving Sniper problems is to figure out if the Sniper is doing what it's programmed to do. If the Sniper is programmed to go to zero timing, then solve that problem. If the Sniper is doing something that it isn't supposed to do, then that's a different problem to solve. Until you know which is which, you can't solve the problem.

[Danny Cabral]

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. I always suggest taking notes of your current distributor's ignition timing specs/curves beforehand, and then program the Base Timing Table accordingly. 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) https://www.efisystempro.com/efi-pro...timing-control (EFISystemPro.com - ECU Timing Control, From Simple To 2D Table)

Overlay the datalog onto your Config File, and pay special attention to the center paragraph in blue print:

Originally Posted by Danny Cabral Quick Datalogger Information: Always provide data, not just symptoms. Is the AFR & ignition timing optimized? Overlay the datalog onto your Config File. Ensure the Target A/F Ratio table is properly programmed for your engine. Ensure the ECU is "Learning" (Learn Table LINK). Scroll through the datalog to the problem area. Then look exactly where this happens on the Base Fuel & Timing Tables. Scrutinize: RPM, MAP, MAT, TPS, CTS, IAC, Target AFR, AFR Left, CL Comp, Ignition Timing, Duty Cycle, Fuel Flow, Fuel Pressure & Battery. When the engine is tuned & running well, you should decrease the Closed Loop & Learned Compensation Limits % to lock in a good tune. Using the Holley Sniper EFI software (LINK), look at where the live cursor moves to during this occurrence, and manually tune that area of the Base Fuel Table (enrich or lean) & Base Timing Table (optimize ignition timing). I find the most helpful datalog function, is overlaying the datalog on your Config File. I'm in the habit of using the datalog Overlay feature every time I review a datalog. Click on "Datalog" (on the top Toolbar), "Activate Overlay", then "Open Data Log". You can literally "playback" a recorded event, and watch it as it happened on any screen. Minimize (shrink) the datalog window, and move it to the bottom of any Config File screen. Then click & scroll anywhere on the datalog, and watch it playback on your Config File (EFI software). http://documents.holley.com/techlibr...9r10543rev.pdf (Holley EFI Datalogger Instructions) https://forums.holley.com/showthread...s-amp-Datalogs (Datalog Information - Read "NOTES") https://www.youtube.com/watch?v=iqHO...C6FEA0BB99AF17 (How To Record & Email A Datalog) https://forums.holley.com/showthread...7531#post77531 (Closed Loop Datalog Tuning - Posts #2, #4 & #6) https://www.youtube.com/watch?v=rHjLwJQ45Kw (Holley Sniper EFI Datalogging Tech Video)

Originally Posted by Danny Cabral For further assistance, post your Config File and a short datalog of this occurrence for us to analyze. Also, review the datalog and inform us of exactly where in the datalog (time/seconds) the problem occurs. Datalog & Global Files can be linked to a document hosting website. I use Dropbox.com. Files can also be "zipped" (compressed zipped folder) & attached directly to a forum post ("Go Advanced" & "Attachments"). Your Config File is in the "Documents", "Holley" folder, "Sniper" folder, "Config Files" folder (.hefi file). Your Datalogs are in the "Documents", "Holley" folder, "Sniper" folder, "Data Logs" folder (.dl file). Someone will analyze/troubleshoot the problem & offer advice. https://www.youtube.com/watch?v=iqHOtDNiTNA (How To Record & Email A Datalog)

[Teambrauss]

I'm watching the data on the 3.5" TSLCD display. Monitoring the TPS, AFR, ECT, RPM, spark. That's how I know the spark goes to 0°. I won't have access to the truck until Monday.

[AndyF]

An engine won't run with 0° of timing at WOT, so my guess is you have some sort of display problem. It'd be interesting to see a datalog to see if the datalog shows the same information. Could just be an issue with the handheld, maybe RFI noise on the CAN Bus or something.

[Chuck L.]

How about posting the tune and a datalog?

[Danny Cabral]

Yeah, see post #4 above.

[Teambrauss]

Here are the files. Thank you.

[a b c]

Did you look at the Base Timing Table? I'm not sure how you did it, but you have all zeros starting at 91 kPa & above. ECUs are great devices. They do exactly what you program them to do. In your case, someone told it to go to 0° timing at WOT! This thread has some links that will help you: https://forums.holley.com/showthread...ferent-Sources. Your GCF needs significant help. Do yourself a favor and don't do anymore WOT pulls until you get it sorted out. If you don't want to get professional help, let us know and we can walk you through it.

[Candu SNO]

I've imported a typical advance curve into your GCF and renamed it. Idles at 19° BTDC, Cruise at 32° BTDC, 36° BTDC at WOT and 42° BTDC on Deceleration. The rest of your GCF remains the same. You can try it out if you like.
GCF 10-20-23 new spark table.zip

[Teambrauss]

I have no idea how I did this either. The truck is sitting in a parking garage until I get this sorted out. I have no experience in this situation. I'd definitely appreciate your help. Thank you, I'll check it out.

[Teambrauss]

Update (11-8-21): That was the issue. The old truck is doing great.