Sequential on 36-1

[Grant Baker]

Hi. 

Just a daft question. 

On a 36-1 wheel, you can set injection and ignition to sequential, even without a cam sensor. 

Is this correct?

[ClintBHP]

No it still needs a cam sync for this as you get a missing tooth every 360 degrees in the 720 cycle.

[Grant Baker]

Exactly. 

So why does it allow it to be selected? 

Runs fine but obviously it’s batch firing. 

[ClintBHP]

The fuel and ignition does not have any checks in it for types of triggers selected - very common.

Also very common for the ECU to default into batched/banked mode in the event of Can sync failure, it’s a good strategy as it allows the e give to run on the first turn instead of waiting for 2 revolutions before starting.

[Adamw]

Actually in multi-tooth/missing mode it will run in full sequential without a cam sensor, it just will not start up without the sync signal present.

It doesnt default to batch fire/wasted spark if cam sync is lost - it only needs the cam signal for startup, once its running (provided the crank signal remains good) the ECU can keep count of phase/position after that. 

At present our generic multitooth/missing mode doesnt do the wasted spark start-up strategy - so it does potentially need to see two full revolutions before it starts firing anything.  Most of our OEM trigger modes will sync in less than one revolution BTW.

[Grant Baker]

What if there is no cam sensor sync selected?

[Simon]

With the CAM sync set to none you will get a 50/50 hit rate if it happens to be on the correct stroke it will run.