Setting up EVO 9 VVC

Mitsubishi EVO plug n play ECU FAQ's

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GEMS Engineer
GEMS Engineer
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Setting up EVO 9 VVC

Post by RickS » Wed Jul 10, 2013 9:03 am

1. Set VVC#n Error table to 0, VVC Out min to 0 and VVC Out max to 100%. If VVC#n Duty is all 50%, and block manipulated to vary the output duty VVC#n Out.
2. Find the range of the Cam#n Angle, the one moved by the VVC valve.
3. Set Cam#n Start so that the useful range is before the lowest Cam#n Angle.
4. Set Cam/VVC Range option to give good resolution of Cam ADV. Note the scaling need not be in actual degrees, a User Scalar might help here.
5. Check, log the relationship between VVC#n Out (Duty) and Cam#n ADV. Note this may exhibit large hysteresis.
6. Average the values obtained, increasing duty with those reducing duty for the same Cam#n ADV. And fill the VVC#n Duty table with the duty values.
7. Fill in the Valve table with a first pass estimate of required advance. Check, log the relationship between VVC#n map, VVC#n Out (Duty) and Cam#n ADV. Note : This may exhibit large hysteresis.
8. Now fill in the VVC#n Error table with a restoring function, Check that the response has improved, you may need to change the VVC FB min or VVC FB max.
9. Now increase from zero the VVC#n FB P and VVC#n FB I PI control loop settings. Note these may be minus.
10. Adjust the VVC#n Error, VVC#n Duty, tables and PI control constants until acceptable control is achieved. Usually a bell error curve will result with a standard deviation of less than 2 degrees is achievable.
11. Now tune the Valve map for best torque or efficiency. Set the VVC#n Stopped and VVC#n Default appropriately for cranking and safe (rich) conditions. You may wish to constrain VVC Out with VVC Out min and VVC Out max, minimise valve heating.
12. To aid tuning a table VVC Fuel mod, may be used to correct the fuelling, for actual cam position. The output VVC Fuel mod with a range of ±50%.
13. VVC target mod, a user adjustable modification of target position with a nominal Calibration range ±80°, may be used to quickly asses the VVC performance.