Opel C20XE/LET 60-2 with CAM sync triggering

[Pet]

Hi all,
I measured a few days back on my bench Vems behaviour, whith 60-2 primary wheel and CAM pulse generated per picture posted in this post.I don't quit understand one thing. Both CAM edges (falling-rising) are aprox. 60deg (rising) resp. 150deg(falling) far from TDC (1&4). Primary trigger tooth I have set to 10, TDC value is then 58 (118deg from gap to TDC). SO it's mean both CAM edges comes after last primary trigger (tooth 10+30) or before new primary trigger on tooth 10.
But what I've found there is difference with spark and ign order generation between those two 2nd trigger settings (raw 24 vs 25).
Do I understand something wrong ??? Thanks

[mattias]

With missing tooth primary trigger the cam sync can appear anywhere as long as it doesn't race with the missing teeth. Unlike a simple primary trigger with cam sync, in this case the reference tooth table and ignition order is referenced to the missing teeth, the cam sync only tells the ECU which of the two revolutions the crank is on so that it can figure out from where to find the first trigger tooth on the 4-stroke cycle (ref tooth = 0).

When you shift from rising to falling edge, you're effectively shifting the ignition order 360 crank degrees, as the signal appears on the next crank revolution.

[Pet]

That's the same what I was thinking for :)
Thanks