VVT
VVT tabs are hidden if the corresponding PWM modes are not activated.
VVT Angle Table
Values are specified in degrees of the crankshaft rotation
- greater than 0 - advance
- less than 0 - retard
For the intake shaft, the position is set from zero to plus (advance). For exhaust shaft - from zero to minus (retard)
Do not set target values closer than 2-3 degrees to the physical limits. This will cause the regulator to stuck in the extreme positions.
If you are using an VR camshaft sensor, make sure the angle is measured correctly. To do this, disconnect the solenoid, and increase revs to the redline. The measured camshaft angle shall be the same over the entire rev range. If the angle changes more than 1-2 degrees, you need to invert the polarity of the sensor.
Calibration
Angle
Calibrates the measurement of the camshaft position angle. To adjust - disconnect the solenoid, start the engine, and adjust the value to achieve measured camshaft angle = 0.
Window
Specifies the window in which the pulse will be read to calculate the angle of rotation of the camshaft. It is used for camshaft pulleys, in which the distance between the teeth is asymmetrical, and / or the number of teeth is not a multiple of the cylinders number.
The window number corresponds to the number of the cylinder in which the ignition occurs. The window starts 60 deg before the TDC of the current cylinder, and lasts up to 60 deg before the TDC of the next cylinder. Window boundaries are indicated by the Trig pulse in the Pulse Input Analyzer.
If set to 0 - the function is off, the cam position is read from every pulse
Corrections
VE
Increases the VE as the camshaft angle increases.
The default value is 100. To increase or decrease corrections proportionally - adjust the value.
If value = 100, the correction is:
| VVT Angle | VE Correction |
|---|---|
| 0 | 0 |
| 10 | 3.6 |
| 20 | 6.6 |
| 30 | 8.9 |
| 40 | 10.7 |
| 50 | 11.8 |
| 60 | 12.4 |
Ignition
Reduces ignition advance when cam angle is increased
The default value is 100. To increase or decrease corrections proportionally - adjust the value.
If value = 100, the correction is:
| VVT Angle | Advance Correction |
|---|---|
| 0 | 0 |
| 10 | -2.3 |
| 20 | -4.3 |
| 30 | -5.8 |
| 40 | -6.9 |
| 50 | -7.7 |
| 60 | -8.0 |
Turn on
Temperature
The engine temperature above which the VVT is enabled. Usually about 30-40g.
Delay
The time after startup after which the VVT is enabled. Delay is necessary to fill the engine oil system.
Configuration
- Enable PWM VVT with a frequency of 300Hz
- PID controller - set defaults
- Set the VVT intake map to +5, the exhaust map to -5.
- Disconnect the solenoids and start the engine. The camshafts will rotate to the default positions (max. intake retard, max. exhaust advance).
- Adjust the calibration angles to achieve measured camshaft angle = 0.
- Connect the solenoids back. The camshafts should turn into their target position.
Adjusting the PID Controller
- Warm up the engine oil to the working temperature.
- Set Kp=0, Kd=0.
- Adjust Ki so that the camshaft is rotated as quickly as possible, but without overshoot.
- Add Kp to speed up regulation, but make sure there is no overshoot. If necessary, reduce the Ki, to achieve the fastest possible regulation.
- Add Kd until the regulator becomes unstable, then divide the value by 2.