Synchronizing Ignition Timing - Holley EFI

[ToysRs]

Danny, I'm chasing some wiring harness gremlins with the 558-117 universal CNP harness, and also getting conflicting info. I've been told that some of these harnesses are incorrectly pinned and that I probably have a "Chevy harness". But I'm running a SBF. The connections are all correct if you go by the white tape labels as far as each coil and the "odd/even" labels. Engine starts, but isn't running right and sounds like timing issue. It's popping and won't stay running. Cam & crank sensors sync and I get RPM signal while cranking. Crank sensor 50° BTDC, cam sync 195° (yes, on compression stroke), MAP looks right, all other sensors look good. This engine ran before with BS3 and nothing mechanically has been altered on the engine other than going to the cam sensor, CNP and Holley Dominator.

Have tried to verify the first 4 cylinders using timing light and injector harness disconnected. #1 is wrong right off the bat. Was given a matrix from someone at Holley, said my harness is most likely pinned incorrectly. So my question is, the "Ford/Chevy" thing gets confusing. So just to clarify here, as long as I'm able to make sure that the wires are pinned per this instruction below, then the harness will be correct and the firing order set in the software will be correct also? If I take my meter and test for simple continuity from each of the B pins and make sure they go to the correct coils, and are in the correct position on the connector going to to the ECU, we should be good, right?
The ECU triggered power (B21, B22, B23, B24, B15, B16, B17, B18) is individually wired to each coil. Holley's 8-cylinder CNP/COP uses all eight ECU triggers.
B21 is always cylinder #1, B15-cylinder #2, B22-cylinder #3, B16-cylinder #4, B23-cylinder #5, B17-cylinder #6, B24-cylinder #7, B18-cylinder #8.
Thank you in advance for your kind assistance.

[Danny Cabral]

Danny, I'm chasing some wiring harness gremlins with the 558-117 universal CNP harness, and also getting conflicting info. I've been told that some of these harnesses are incorrectly pinned and that I probably have a "Chevy harness". But I'm running a SBF.

That only pertained to some of the early Holley 558-312 CNP coil pack sub-harnesses sold (LINK). It doesn't pertain (& never did) to the Holley 558-307 Coil-Near-Plug main harness.

So just to clarify here, as long as I'm able to make sure that the wires are pinned per this instruction below, then the harness will be correct and the firing order set in the software will be correct also?

Yes.

If I take my meter and test for simple continuity from each of the B pins and make sure they go to the correct coils, and are in the correct position on the connector going to to the ECU, we should be good, right?
The ECU triggered power (B21, B22, B23, B24, B15, B16, B17, B18) is individually wired to each coil. Holley's 8-cylinder CNP/COP uses all eight ECU triggers.
B21 is always cylinder #1, B15-cylinder #2, B22-cylinder #3, B16-cylinder #4, B23-cylinder #5, B17-cylinder #6, B24-cylinder #7, B18-cylinder #8.

http://documents.holley.com/techlibr...10555rev17.pdf (Holley EFI Wiring Manual - Section 2.1 "Pin-Outs", Pages 6, 7 & 8)
http://documents.holley.com/199r10515rev3.pdf (Holley 558-307 CNP Main Harness Wiring Instructions - Ford Engines, Page 2)

Originally Posted by Danny Cabral Ignition Timing Cylinder Sequence Verification Ensure the Firing Order is entered correctly in Ignition Parameters (System ICF). Before the initial start, disconnect the fuel injector harness and verify at least, the first four cylinders in the firing order using a timing light. If your cylinders are firing in 90° intervals BUT in the wrong sequence, the coil harness is connected wrong (at the ECU or at the coil packs). Hopefully you have a fully degreed balancer or at least markings every 90°: 1st cylinder, in firing order, should fire at 0° (or 15° - add whatever your cranking timing is) 2nd cylinder, in firing order, should fire at 270° (or 285° - cranking timing added) 3rd cylinder, in firing order, should fire at 180° (or 195° - cranking timing added) 4th cylinder, in firing order, should fire at 90° (or 105° - cranking timing added) 5th cylinder, in firing order, should fire at 0° (or 15° - cranking timing added) 6th cylinder, in firing order, should fire at 270° (or 285° - cranking timing added) 7th cylinder, in firing order, should fire at 180° (or 195° - cranking timing added) 8th cylinder, in firing order, should fire at 90° (or 105° - cranking timing added)

FORD engine cylinder numbers:

GM & CHRYSLER engine cylinder numbers:

[ToysRs]

Thanks VERY MUCH for the quick response and for all you do here Danny. God Bless.

[Danny Cabral]

You're welcome, and thanks for the compliment.

[ToysRs]

Looking over the tech info, I'm just asking for the sake of others that might stumble across this Danny. I have the Universal MPFI/CNP Main Harness 558-117: https://documents.holley.com/558-117...ss_diagram.pdf. Looking at the pin-out info from the Wiring Diagram document: https://documents.holley.com/199r10515rev3.pdf. B21 is coil #1, and on the main harness diagram, B21 is on the ODD connector (1-3-5-7). But the instruction sheet (pin-out diagram) says for FORD that B21 should be on the EVEN connector (2-4-6-8). So it does appear that these harnesses are pinned for GM/CHRYSLER out of the box.

[Danny Cabral]

So it does appear that these harnesses are pinned for GM/CHRYSLER out of the box.

Yes, because you have a SBF and didn't purchase the Ford Universal MPFI Coil-Near-Plug Main Harness: https://www.holley.com/products/fuel.../parts/558-118 (Holley EFI 558-118 Ford Universal MPFI Coil-Near-Plug Main Harness)

[ToysRs]

Mystery solved. I ordered this stuff from a Holley dealer, and did indicate I have a 427 small block Ford.

[Danny Cabral]

I'm glad we got to the bottom of this. Most people find this document very helpful: http://documents.holley.com/efi_sele...chart62914.pdf (Holley HP & Dominator EFI Component Selection Guide)

[ToysRs]

I realize things are always evolving, and as a fellow Ford guy, I'm sure you can relate to what I'm about to say. On that document, nowhere is there any reference to either the 558-117 or 558-118. I wish I had known about the 558-118. Seems the Ford info is scattered and hard to keep track of. Adding to the confusion, is that the 558-117 actually has labels on the coil harness connectors that say "FORD" on them, but they're incorrect. They also refer to "ODD" & "EVEN", but Fords have even & odd numbered cylinders on both banks. Bottom line is there's still some info lacking on these products. I don't blame my dealer for steering me to the 558-117 initially, as it clearly is referred to as "UNIVERSAL" and the Ford tags caused me to let my guard down. Before installing this harness, I looked over everything, familiarized myself with all the connections, and thought all I had to do was plug it all in and be done with that step. If there hadn't been any "FORD" tags on the connectors, that at least would have given me pause to say "Hmm maybe I have the wrong harness here". Now when you compare the coil harnesses on the 558-117 & 558-118, it's clear that they are pinned differently. Four coils are not pinned the same way, yet the tags are there for FORD on that 117 harness. This should be corrected or removed, so guys like me don't rip out what hair is left on their heads trying to chase misfire issues. This document DOES have some useful data on the 558-117 & 558-118 main harnesses: https://documents.holley.com/techlibrary_199r11401.pdf. Anyway, hopefully any Ford guys that stumble across this topic will benefit from the info.

[hegill]

I've read this article about synchronizing Ignition timing several times. While I understand most of it, there are a few things I don't understand. I'm using a GM small cap HEI distributor on my truck with a Holley Terminator TBI. When it was setup with an original GM TBI throttle body & ECM, I had to disconnect the timing wire so that the computer would NOT control the timing then according to the manual I had to set the base timing at 0°. I'm pretty sure that the ECM then advanced the timing on the GM setup beyond 0° when the timing wire was reconnected.

I know that the Cranking Timing according to the Holley software is 15° and that I should ensure that the timing when used with a timing light and cranking without starting the engine should match this value.

What I don't understand is:
1) What's the timing supposed to be at idle with no advance on the Holley EFI setup?
2) In the manual for the 3.5" handheld it shows a picture where the ignition timing at idle is 20°, but then says that for the idle timing typically anywhere from 18 to 34° is used. Do these values represent the Static Timing plus the advance that the ECU adds?
3) How can I determine what the actual timing is at idle with no advance, if this is a combined value?
4) If the ignition advance values need to be changed, is that done in the base timing graph or Base Timing Table or somewhere else?

[Danny Cabral]

I know that the Cranking Timing according to the Holley software is 15° and that I should ensure that the timing when used with a timing light and cranking without starting the engine should match this value.

Correct: http://forums.holley.com/showthread....ents-Read-This (Initial Checks & Adjustments - Read Step #4)

What I don't understand is:
1) What's the timing supposed to be at idle with no advance on the Holley EFI setup?

There's not "no advance" in the Holley EFI software. With a GM HEI & Ford TFI, simply set the Ignition Reference Angle to 10° and forget about it (it's not your idle timing).
http://www.masterenginetuner.com/top...all-fails.html (Crank Reference Angle Importance)

2) In the manual for the 3.5" handheld it shows a picture where the ignition timing at idle is 20°, but then says that for the idle timing typically anywhere from 18 to 34° is used. Do these values represent the Static Timing plus the advance that the ECU adds?

No, the Static Timing synchronization feature (temporary EFI software tool) is exactly what's entered. And the ECU controlled timing (Static Timing synchronization feature off) is exactly what's programmed in the Base Timing Table. If you're referring to static timing as the initial timing (no vacuum advance), then you must specify that because Static Timing means something different in the Holley EFI software. It's a temporary EFI software tool for synchronizing the ignition timing.

3) How can I determine what the actual timing is at idle with no advance, if this is a combined value?

Believe the timing light above all else, it's always the real timing (if there's a discrepancy).
When finished, the timing as viewed on the laptop, should match what you see with the timing light, at all RPM.
Once the ignition timing is fully synchronized, the Timing Table can be tuned for each application.

4) If the ignition advance values need to be changed, is that done in the base timing graph or Base Timing Table or somewhere else?

Once the ignition timing is synchronized, all timing tuning changes are performed in the Base Timing Table. The Timing Graph is just an EFI software visual aid for the end user.

The ECU needs an Ignition Reference Angle, so it can control the timing. (10° Ignition Reference Angle is correct for GM HEI & Ford TFI. The GM HEI & Ford TFI distributors are installed at 10° Ignition Reference Angle, but they're operating one crank revolution ahead, so they're retarding a lot. On a high RPM race engine, it's best to keep the amount of ignition retard (occurring from such an advanced reference angle) to a minimum, so it's not used on expensive race engines. Of course, timing accuracy is better with a crank trigger.)
http://www.masterenginetuner.com/top...all-fails.html (Crank Reference Angle Importance)

Example: An EFI distributor doesn't have a centrifugal advance & vacuum advance mechanism; that's all locked out if converting an old carbureted distributor to ECU controlled EFI ignition timing. So the initial & vacuum advance is combined in the "Idle", "Cruise" & "Deceleration" areas of the Base Timing Table: