V3 primary trigger settings

Subpage of Base setup menu


Primary trigger settings

Trigger Edge
Always rising for VR type sensors, typically falling for Hall sensors.

Changes to Trigger Edge, when burned to ecu, are applied on next ecu powerup; make sure to power cycle the ecu for changes to take effect.

Trigger Type
Coil-type is for all trigger setups without missing tooth.

Missing Tooth Type
Set how many missing teeth you have on your trigger wheel in one crank rotation.

Special Trigger Type

  • Lancia Cosworth
  • Fiat Stilo, Subaru
  • Audi Divby3 : for 135 teeth on the flywheel, divides total tooth count by 3 to handle the large teeth count.
  • Audi Divby2 : For other Audi type trigger wheels not evenly divisible by 3

TDC After The Trigger
Number of crankdegrees from the trigger tooth to TDC. This is where you calibrate the ignition angle using your strobe light. Recommended range between 60 and 80 degrees; Absolute minimum minimum 40 degree, some motorbikes needs ~10degree for cranking

Number Of Teeth On Wheel and Number Of Teeth Of Full Engine Cycle
If your firmware version is

  • >= 1.1.90
    • For Trigger Type = Missing-tooth, Number Of Teeth On Wheel is enabled: the number of actual teeth on your trigger wheel
      Example: 58 teeth for a 60-2 wheel.
    • For Trigger Type = Coil-type, the Number Of Teeth Of Full Engine Cycle textbox is enabled: the number of primtrig pulses (divided by divider if divider is enabled) between secondary trigger pulses (usually the number of crankwheel teeth * 2)
  • < 1.1.90 you see only Number Of Teeth On Wheel
    In case of
    • Missingtooth: number of actual teeth on your trigger wheel
      Example: 58 teeth for a 60-2 wheel.
    • Coil-type: number of teeth of full engine cycle (2 * number of actual teeth on your trigger wheel)

First Trigger Tooth ("FTT")
This determines what tooth to start counting TDC After The Trigger from. Must be less than NTT (Next Trigger Tooth) (and less than NTT-1 for N-1 wheel; less than NTT-2 for N-2 wheel). The first actual tooth after the missing tooth (gap) has index 0. If TDC after the trigger is outside of recommended range, adjust first trigger tooth. On 5 cyl (or odd number of cyl: 3 cyl, 7 cyl) consider this: FTT + N*next_trigger_tooth must not point to nonexistent tooth. Eg 10 or 11 will not work, because +2*24=58 (or 59) => nonexistant tooth on 60-2.

Next Trigger Tooth
Enter the number of teeth between cylinder events.
Example: On a 4 cyl 4-stroke engine with 60-2 wheel, this value would be: total_teeth (actual+missing) / number_of_cyl = (2 * 60) / 4 = 30.
Remember to set the tooth reference table!

Angular Width Of Tooth
Actual angle between two teeth on the wheel.

Example of angular width of tooth

  • 60-2 the toothwidth is 360/60=6 degrees
  • 18-1 where a tooth is 360/18=20 degrees
  • 36-1 where a tooth is 360/36=10 degrees
  • 10+1 (5 crank+1 cam) where a tooth is 360/5=72 degrees
  • 24+1 (12 crank+1 cam) where a tooth is 360/12=30 degrees
  • Audi 270+1 (135+1 crank+1 cam) divby3 where a tooth is 360/45=8 degrees
Generally value should be 360/(Number of teeth per crank rotation (+1 or 2 if missingtooth))

Delayed reenable filtering
The simple filter is mostly used for coil-type trigger, do not use with missing-tooth triggers. It disables triggering for the first half of the trigger period to avoid noise problems.

RPM filter, cam based trigger
Applies filtering on RPM reading by 3 periods, this helps when triggering from CAM which might suffer from unstable period from belt slap/chain rattle. Recommended on Nissan Triggers.

Advanced Filtering
This is only for missing-tooth, you can specify the relative time difference allowed for a normal tooth and the missing tooth.

RPM can change relatively much during 30 degrees (12 cranktooth) during cranking, especially with a high compression engine. Not an issue with 60-2. We had to enable multitooth advanced filter on a home-grinded 12-1 (made from 12 tooth) VR trigger to crank. Otherwise the normal toothtimes (as shown by external triggerlog analysis) were sometimes x1.59 or even x1.62 of previous tooth, therefore misdetected as missing tooth by the normal 150% threshold -> no start. 175% threshold seems to work: missing tooth was between x2.02 to x2.31.

These are the settings for the advanced filter:

  • Tooth Normal Relative min % : Minimum % compared to last tooth time to consider as normal tooth, not missing.
  • Tooth Normal Relative max % : Maximum % compared to last tooth time to consider as normal tooth, not missing.
  • Tooth Missing Relative min % : Minimum % compared to last tooth time to consider as a missing tooth.
  • Tooth Missing Relative max % : Maximum % compared to last tooth time to consider as a missing tooth.

Example of advanced filter settings
x-1 trigger, Normal=25..169%, missing=169..288%
x-2 trigger, Normal=25..175%, missing=200..413%

For 12-1 missing tooth wheel "advanced missing tooth filter=enabled" with normal_tooth_max=175 and missing_tooth_min=175 recommended. (especially if it does not start with cranking, and trigger wheel errors occur. Try triggerlog during cranking).

Explanation: RPM can change relatively much during 30 degrees (12 cranktooth) during cranking, especially with a high compression engine.

Special extra pulse trigger: This needs to be used on engines which instead of a missing tooth, have an extra tooth to sync; Best known are Honda F20/K20 engines.

Hall dirac filtering: In some installation with Hall sensors there can occasionally exist very small noise pulses (like dirac pulses). Use only for problematic, noisy low toothcount Hall sensor with max 24 teeth AND trigger signal stays minimum 10 crankdegrees after chosen edge. It is not recommended anyway, unless it is really needed.
Must not be set for VR trigger at all.

For other special triggers use the configlets below this dialog.