Link's G4 multitooth decoding/use?

[Ivaylo Angelov]

Hi Simon,

A rarely asked question but it's interesting imho. Recently I had a small dispute with a friend concerning the actual use of the multitooth target as a crankshaft position decoding by the different ECU manufacturers. One of the points was the multitooth count is reduced to much lower count (depending on number of cylinders) by the ECU code and then all the engine controls i.e. spark timing, coil charging...etc calculations are based only on the time interval between these low count teeth. Something like software dizzy. I've seen similar statement in the Vi-Pec forum by Ray Hall, long time ago, where he stated it's not important for the ECU if the tooth count is more than 24 or sort of.

The other point was the ECU code is counting on every tooth for engine controls, i.e. the spark timing, coil charging...etc is based on tooth count plus time interval since the last tooth. 

Please, would you shed some light on how mutitooth target is used by Link G4?

Thanks in advance!

[Dave Kriedeman]

Hi,

multi tooth or multi tooth  missing tooth patterns alone or multi tooth , missing tooth with sync sensor.

This is a very sparse topic and being more specific will reduce the reply subject written.

Please state which type.

Regards

Dave.

[Simon]

With multi tooth up to a point we are using every tooth to update the position / RPM

If it is a very high tooth count such as some BMWs or Porsche applications (more than 60 teeth) 

We then start dividing the tooth count down to a more manageable count.

[Simon]

If there is a 60-2 or a 36-1 option that bolts up from say a later version engine then theses would be the go.

However if you were needing to fabricate a trigger then I would go to a 24-1 as this will be easier to make and gives plenty of resolution.