| What you got wrong is how the ecu uses the missing tooth. Ill try to explain . Say you got a plain 36 on the crank and a single sync on the cam... The engine is chugging along. The cam tooth passes the sensor whom in turn shouts out to the ECU "HEY DUDE! Reset/Start counting NOW!". The ecu now starts looking for the NEXT falling edge, sees it and all is dandy. It goes 1 tooth - 2 tooth - 3 tooth FIRE 1! - 4 tooth ------- 34 - 35 - 36. Then the CAM comes online again "HEY DUDE!....".
What can happen is, as you correctly imply, is that the ECU goes --- 34 - 35 - "HEY DUDE!!!.... Wait, what??? So either the ECU then goes "Alright! 1 - 2 - 3" and then fire 10 degrees off. OR it throws its hands up in the air going "I have no clue whats going on here! I quit!" then shuts of until it get up to speed with shit again. So yeah you got that one right. What is important when setting this system up is getting the cam set smack in the middle of 2 of the crank teeth. As you said with 36 you have 10 degrees between them. On my own car i have seen about 7.5 degree slop between the crank and cam triggers (on a scope). And there might be more. But thats what i saw inside a very small sample i took during a pull. So there isnt much room for error with just 10 degrees... Now imagine you got a 36-1 on the crank and a single on the cam instead.
Cam goes "HEY DUDE! Here is the cam sync! Reset/start counting when you are ready". ECU goes "Alright bud! 31 - 32 - 33 - 34 - 35 - There is the missing tooth! Awsome! 1 - 2 - 3 - Fire 1!....". So in this last example the ECU only uses the cam sync signal to detect which stroke the engine is on to be able to run in sequential mode. The timing on the cam in relation to the crank trigger, and missing tooth, is far less critical as the ECU uses the missing tooth as a reference for its "reset" signal. Not the cam signal as is used in example 1.
HOWEVER you do NOT want the cam signal to trigger at the same time as the missing tooth! As you can upset the ECU with that. In my opinion more crank teeth is better. As more resolution (on a stable accurate base) is always better. Regardless what some might say (and DO say). But as always there are variables. Some ecus dont use all the teeth on a high toothcount wheel. They are COUNTED but not used for timing calculations. So they are just wasted really. Then there is that issue that some HALL sensors (if thats what one wants to use) dont do to well with high toothcount. Some also have problems with missing teeth. For these reasons in could be wise to look into a VR sensor instead especially when going high toothcount. Personaly i am on a GT101 HALL sensor on a 24-1 wheel and it havent missed a beat this far. But dont think i would go much higher for that sensor. Maybe 36 is OK. But havent tested it so not guaranteeing anything.. Hope this clarifies shit a bit..
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