Adaptronic Confusion... Reset Trigger

Hello!

I wonder if anyone might have an insight on this... in the worked example from the FD3S in the PST course the Reset Trigger is specified as Crank mounted with a 360 degree reset. This makes perfect sense to me, the wheel is mounted on the eccentric shaft and the single tooth passes the sensor once every 360 degrees of rotation.

When looking at the settings in the base map (and several "mapped" cars) it would appear that for a Select ECU this is set to 720/CAM which somehow doesn't seem right. Checking the Modular Base Map indeed shows 360/CRANK....

I'm trying to understand the reason for the disparity given that both ECU's are referencing the same engine/sensor combination and I'd been keen to understand the implications of the difference.

Many Thanks

Dave

At a guess, it's late here, it's because the timing counts crank degrees from the crank trigger, to establish TDC, and depending on the trigger position it may need to make more than one full revolution to establish the correct start point.

The camshaft rotates at half crank speed, with two rotations - 720 degrees - of the crankshaft to one - 360 degrees - at the camshaft. This means to ensure the reference trigger for which crankshaft revolution it's on (intake-compression, or power-exhaust) the crankshaft has to make two full revolutions.

For sure on a piston engine that would make sense but I don't think that's quite the same on a Rotary.

Surely if the tooth passes the sensor it creates a trigger event, and the single tooth in this case is mounted onto the eccentric shaft.... the software has the down as 720 degrees of completed rotation that doesn't seem right.

Perhaps it makes no difference because the front and rear rotors would have both completed an ignition event in 360 or twice in 720 degrees and as such there's not really anything to be concerned about... from changing the setting and running an engine with it both ways I can tell no difference. I'm interested to understand the logic, the reason for the difference and what if any impact it would have.

:)

I've not used Adaptronic, so this is just a guess, but it seems something specific to how Adaptronic set up their software. It likely makes sense to the engineer that wrote the code, but perhaps isn't clear in terms of mechanics of the engine. Maybe it's related to how their ECU deals with direct vs. wasted spark, despite that not being related to triggering settings in other ECUs?