I already have a VEMS V3.8 ECU with auditrigger/camhall inverter (suitable for VR/VR and VR/auditrigger)
Installing Audi 4.2 Liter V8 ABH code engine.
The engine has Auditrigger (every 2nd sectrig VR pulse masked by cam-HALL) like Audi AAN.
- Primary (VR)trigger, RPM sensor are sensing 136 yes 136 teeth on starter ring
- Secondary (VR) trigger are sensing the TDC point. 72° before TDC.
- Camshaft HALL window for masking sectrig. 1 small window wheel (short 0V and long 5V ?), like on 3B or AAN.
- note: this is NOT the same as "third trigger" (third and fourth and fifth triggers are connected to specific inputs)
- so avoid "3 trigger" naming because that is reserved for real 3 trigger setup which VEMS also supports (with variable camshafts; Upto 4 variable camshafts and 5 triggers).
c272: 272 teeth on full engine cycle, so 34 tooth between events:
- divider=17, number of teeth on wheel=16 ; next trigger tooth=2 (I would use this "divby17": after the divider, setup is similar to c016 : 16 primtrig pulses for 1 sectrig pulse)
- reftooth sequence steps by 2 each time: 0 2 4 6 8 a c e
- this setup is very similar to the c270 (135 tooth) with divby27 which has been benchtested beyond 14000 RPM
- divider=2, next trigger tooth=17
- number of teeth on wheel=136 (might or might not work: >128 so it might internally mis-state as "resync").
- Only try divby2 as "last resort".
Can this trigger setting work?
Will check your annotated vemslog.
Please publish triggerlog (obviously that is the way to proceed during trigger setup (even when it goes smooth without issue).
When capturing triggerlog, if configured for auditrigger, some pulses might be hided.
- so if not starting anyway, and capturing triggerlog at cranking RPM (<200), maybe a good idea to cheat, and configure normal (eg. 60-2 or coil type without divider) trigger to see events
- eg if one tooth is broken and causing problems (it happened before), that might be very good to see
- do not save that "triggerlog cheat config", or save with very characteristic name (so you and whoever helps you know that config was only used for triggerlog, not for startup attempts !)
- and do not forget to configure auditrigger + divider after triggerlogging.