MSefi.com read only forum (Jan.15,2018)

The crank reluctor ring has 7 notches, 6 of which are evenly spaced (i.e. 60° apart) about 3/16" wide (5mm) and 1/4" deep (6mm). One additional notch is placed ion the ring to 'sync' the module to the engine's position. This sync notch (the sync pulse) is retarded by 10° from nearest notch.

* In a 6-cylinder application, the evenly spaced notches coincide with TDC. The sync pulse notch coincide with 10° after TDC for the #1 cylinder.



Trigger Wheel Settings:
Trigger Wheel Teeth (teeth) ___
Missing Teeth (teeth) ___
Skip Teeth (teeth) ___
Delay Teeth (teeth) ___

The only thing I think I figured out is the trigger offset is 10°, can anyone help with the other settings

The Megasquirt does not read this trigger directly - instead, it works through a GM DIS module that passes it a HEI-like signal. So you won't set up the wheel decoder with this application.

Matt Cramer wrote:The Megasquirt does not read this trigger directly - instead, it works through a GM DIS module that passes it a HEI-like signal. So you won't set up the wheel decoder with this application.

Okay another question do I set the trigger offset to 10.0° or to 0°

I'm running a GM 6cyl DIS system on my Z24 using MS2. On my set-up, I found that my engine would stall when I plugged in my bypass relay with the trigger offset at 10°. I found that I needed to set the trigger offset to 60° in order for the timing showing on MS2 to match the reading seen by the engine.

I got my engine up and running by running the DIS in 'base timing' or bypass mode. This was helpful to me because I knew then that the problem with the engine dying was due to grossly incorrect timing (once I connected the bypass relay), not some other tuning issue. My car did not have a factory timing pointer, so I made one and used a TDC stop to precisely locate TDC on my balancer. I then printed degree wheel off of the internet and taped it to my balancer. Then I just verified that my MS2 read the timing showing up from my timing light. I suspect that the 60° trigger offset is something built into the DIS, but I cannot explain exactly why I needed it set this high.

I'm wondering if others have found that they need to do this or if I have something else set up incorrectly? Its been working great for me so I haven't been worrying about it.