V3 camshaft angle control
Subpage of Motorsport menu
Camshaft angle control ( control intake and exhaust camshaft angle position )
- When Camsync is enabled, the intake Cam (secondary) trigger position is measured and logged.
- When Third trigger input is enabled, the exhaust ( or Subaru boxer left intake ) Cam trigger position is also measured, using the processor SDA pin, see below
- The PWM output solenoid is controlled with a PID controller
- Alternatively (dual Vanos) two outputs are used ( eg.: configured ign2,3 ign2= advance / ign3= retard )
- The control works above 450 RPM. Else (eg.: when engine stalled ) output duty cycle=0.
- Usable triggers:
- Primary trigger:
- missing tooth type, camsync: coil-type and third trigger:coil-type
- OR (BMW dual Vanos) Primary trigger: missing tooth type camsync: extrapulse-type and third trigger: coil-type ( last pulse measured )
- OR Primary trigger: coil-type camsync: coil-type and third trigger: coil-type
- OR (Honda) Primary trigger: extrapulse-type camsync: extrapulse-type and third trigger: coil-type ( last pulse measured )
- OR Primary trigger: Subaru 36-2-2-2 camsync: Subaru special and third trigger: Subaru special
- OR Primary trigger: Suzuki 36-2-2-2 camsync: Suzuki special and third trigger: Suzuki special
- Any other trigger combination is unsupported.
- Primary trigger:
- Measuring method:
- In general, the "measure tooth" should be configured, so the sectrig (and third trig) position measures 5-35 degrees normally (that means appr 40-75 when fully advanced. For example 100 degrees is too high, just lower "measure tooth", and the target table should be lowered accordingly to match the measured values, of course),
- Missing tooth type:
- the Camshaft tooth measured to the Tooth count configured in the "Measuring at tooth_cnt" (first tooth (tooth_cnt = 0 ) is the first after the missing tooth)
- for example cam angle = 345 degree, measuring at tooth_cnt = 0:
- Missing tooth type with extrapulse cam ( BMW dual Vanos ):
- the last camshaft tooth measured before the Tooth count configured in the "Measuring at tooth_cnt". (Tooth_cnt = 0 is the tooth right after missing tooth).
- the 6+1 extra pulse (exhaust-cam) trigger must be connected to secondary trigger, the evenly-spaced 6 pulse (intake-cam) connected to third trigger input (so the "exhaust target" table is actually for the intake)
- for example cam angle = 10 degree, measuring at tooth_cnt = 14 (this is just an example, measure tooth is usually lower, see above):
- Coil type:
- the Camshaft tooth measured to the Tooth count configured in the "Measuring at tooth_cnt", next primary tooth is Tooth count = 0,
- so maximum angle difference can be measured is tooth width
- for example cam angle = 345 degree(but it is bigger than 72 deg so 345 modulo 72 = 57), measuring at tooth_cnt = 0:
- Coil type with extrapulse cam ( Honda ):
- the Camshaft tooth measured to the Tooth chosen by "Measuring at tooth_cnt" variable. Tooth count = 0 is the primary pulse after the primary extrapulse after the valid sectrig sync pulse. With the actual triggerlog (different than this example-shot), good values are apparently measuring at tooth_cnt = 4,10,16 or 22 but rather 5,11,17 or 23.
- the 4+1 extra pulse trigger must be connected to secondary; the evenly placed 4 pulses to third trigger input
- Example: exhaust cam angle = 31 degree, cam angle=156 degree, measuring at tooth_cnt = 4:
- Subaru 36-2-2-2 under fw 1.1.92:
- the first Camshaft tooth (after the long gap) measured to the Tooth count = 0
- for example cam angle = 345 degree:
- Subaru 36-2-2-2 above fw 1.1.92:
- Suzuki 36-2-2-2 above fw 1.1.92:
- Configuring parameters:
- The PID parameters, PWM period and Output type are common to exhaust and intake camshaft control.
- The PWM period: 25Hz to 375Hz
- The output channel and reference position can be set separately to each camshaft control ( for single PWM only )
- For exhaust control the third trigger input must enable and reboot ECU to enable position measurement.
- The target can be set in the target tables (located in the menu under this dialog).
- Dual Vanos Output type:
- Two outputs used for intake and two (optional) for exhaust.
- Use injector or ignition output ( 4ohm => 3A current )
- Control method:
- Under 450 RPM : OutputA and OutputB inactive
- Measured = 0 ... target - 2 deg - PWM-ing range : OutputA active and OutputB inactive , Cam pulse too late
- Measured = (target - 2 deg - PWM-ing range) ... (target - 2 deg) : OutputA active and OutputB PWM-ing ( closer to target = PWM duty higher )
- Measured = (target - 2 deg) .... (target + 2 deg): OutputA and OutputB active
- Measured = (target + 2 deg) .... (target + 2 deg + PWM-ing range): OutputA inactive and OutputB active
- Measured = (target + 2 deg + PWM-ing range) ... 360 deg: OutputA PWM-ing ( closer to target = PWM duty higher ) and OutputB active , Cam pulse too early
- Third trigger input electrical specifications:
- The third trigger is a processor input pin without any protection.
- To set it up, use Pull-up resistor and protection Diode.
- The Firmware 1.1.81 has different way, see the details here
.