12-1 sensor setup VR4/DSM

[Dan P]

I want to setup my 12 tooth crank trigger as a 12-1 for the purpose of ignoring the cam sensor after the engine starts.  I just don't like the idea of relying on old cam sensors(my crank sensor/wheel is a new Kiggly unit).  Seems like the pros are doing it this way on other systems, is it possible to ignore the the cam sensor? (Don't want batch fire)

[Adamw]

Yep, will stay in sequential if cam sensor is lost.  It will even start up in sequential with no cam sensor (but will only start approx 50% of attempts).  

Although any tooth could be removed, I would suggest the tooth that is under the sensor when the crank is at about 90BTDC or 90ATDC will be the best option.  

[Dan P]

6 hours ago, Adamw said:

Yep, will stay in sequential if cam sensor is lost.  It will even start up in sequential with no cam sensor (but will only start approx 50% of attempts).  

Although any tooth could be removed, I would suggest the tooth that is under the sensor when the crank is at about 90BTDC or 90ATDC will be the best option.  

I am not so worried it loses sync as I am it will give false cam position data..and put the ignition timing where it's not supposed to be.  I think a great feature would be to disable it after startup.

[Adamw]

Ignition timing comes from the crank wheel not the cam wheel.  As long as the crank signal is good the ecu doesnot need the cam sensor once it is running.  It will only need the cam signal to resync if it losses crank position.  

[Dan P]

Is this true for a crank trigger with a missing tooth only?  Or can I just run my 12 tooth without modifying it and it will operate like you mentioned above?  Thanks.

[Adamw]

Multitooth will still keep running without the cam but it is much less foolproof or safe.  The missing tooth means you get a position confirmation once per crank rev.  Multitooth with no cam just has to rely on keeping count.