¶ Intake & Exhaut VVT
The Intake and Exhaust VVT (variable valve timing)work in a similar manner. The VVT menu has three tabs; below, we will look at each one separately and explain the main settings.
The VVT algorithm can work in both Open Loop and Closed Loop modes. When using Closed Loop, the main table is a target angle table. When using Open Loop, the main table is a duty cycle target table; in this mode, the PID settings are ignored.
On the right-hand side of the menu, there is a real-time monitor of VVT-specific variables.
- ENABLE: Enable/Disable VVT
- PWM frequency: VVT Solenoid control frequency
- PWM Output: Output used to control the solenoid
- Control Range: Maximum and minimum control angle (advance and retard)
- PWM Output Inverted: If the control duty cycle goes from 0-100% or 100-0%
- Activate only when Runing: If the VVT should stay OFF until the engine is started
- Algorithm Sellector: If the output includes the PID algoritm (closed loop) or if the table value is directly connected to the Output (Open Loop)
- Table: If in Closed Loop please use advance/retard angle values on this table, if using Open Loop please use Duty Cycle % values on this table
- PID Settings: P I D Values for the Closed Loop mode, the Option ''compute on measurements'' updates the PID Values every time the ECU reads the CAM angle, if this option is not sellected the PID values are updated based on the time configured above on the ''loop speed'' variable
- PID OUT Limits: This are the Duty Cycle limits for VVT control, this will constrain the control between the Maximum and Mininum Values, in most enginesn that have VVT the solenoid will only move the CAM when the duty cycle applied is above or below a certain value, the ''HOLD'' value is the duty cycle value that in theory will HOLD the CAM at a certain angle.
- PWM frequency: VVT Solenoid control frequency
- Offset: This is the value required to reset the angle to zero, when the engine starts with the cam on the ''relaxed'' position RM-Tuner will report the CAM angle, without the OFFSET value you would have to ADD or Subtract the required advance/retard angle from this, it would be extremely confuse to work with such big numbers, to make your life easier disable both VVT's, go to Settings->Engine Config and click on the Crank sensor Tab, check the CAM angle values didsplayed on the highlighted boxes (image below) write them down as the OFFSET for each one of the VVT controls
- Dead band: VVT is a system based on a hidraulic system, with engine wear and tear certain systems will have a little bit of flutuation, 2-5 degrees, to avoid trying to compensate for this at all times you can set a dead band and the ECU will ignore small deviations and only correct above that.
- Min RPM: The minimum RPM to activate the VVT control
- MIN CLT: Minimum coolant temperature to actviate the VVT control
