Trigger wheel

[Ken Dunkley]

I have a 60-2 trigger wheel on my car and have a single tooth trigger in the dizzy for a sync . All works very well and no errors . But is it possible to run a trigger wheel with 2 evenly spaced gaps 180 degrees apart . My thinking is if i could run this pattern it would sync within 360 degrees . If a gap on the wheel occurs and no dizzy sync pulse occurs or if the gap on the wheel occurs and then a dizzy sync pulse does occur the ecu will know where it is in the cycle and it should sync within 360 - Should it not ?  Would this work on a link G4+ Atom ?

[Adamw]

Your theory is sound but it wont work with your generic trigger setup.  Since your trigger 2 sync mode is set to "cam pulse 1x", the ECU will only sync after it has seen a cam pulse.  The other problem with our ECU (and most aftermarket ECU's) is they will only start firing from No1 cylinder, so even if you did achieve sync earlier, the ECU would still not start firing until No1 cylinder comes around again.

For your interest though, many OEM trigger systems do work the way you describe - by using unique patterns on the crank it can work out crank position much faster then as soon as it knows what the crank position is it will look for certain edges or levels on the cam and will have 720 sync right away. From there some ECU's will instantly start firing the next scheduled cylinder while others less sophisticated just switch to batch fire/wasted spark mode and start firing when the first No 1 TDC comes around next (regardless of which stroke).  

I have a feeling our "Cam level" sync mode may sync within 360deg but I would have to confirm that with engineering as I dont know for sure.

The easiest solution for you will just be to turn off trigger 2, then it will sync within 360deg with no hardware changes. 

[Ken Dunkley]

Thanks for the answer and the info - cheers .

[Simon]

Cam level mode will sync in a half cycle it looks to see if the cam signal is high or low as the gap goes past and then knows the stroke.