Boost Control Long Term Trim

Boost Control Long Term Trim

This node allows you to enable, disable and reset the long term trim learning in the ECU.

Enable Long Term Trim - Enables the Long Term Trim control.

LTT Min TPS - Long Term Trim control is active only when the TPS is greater than this amount. This is to ensure learning is only possible during stable boost conditions.

LTT Min RPM - Long Term Trim control is active only when the RPM is greater than this amount. This is to ensure learning is only possible during stable boost conditions. i.e. to not learn when the Target Pressure is not possible to be reached. 

LTT Max RPM - Long Term Trim control is active only when the RPM is greater than this amount. This is to ensure learning is only possible during stable boost conditions. i.e. when turbo efficiency can cause the Target Pressure not to be reached.

LTT Min Gear - Long Term control is active only when the vehicle is in this gear number or higher. This is to ensure learning is only possible during stable boost conditions, such as a turbo that has not reached operating speed in a lower gear.

Reset - Resets all Long Term correction tables back to zero for all values.

Apply To Base Table - Applies any Long Term corrections to the Closed Loop Base Duty table, and after applying these changes it will reset to zero for all values. 

Boost Control Long Term Trim Gain Table



This table controls the rate at which the Long Term control can make corrections to the Long Term Trim table. Larger numbers will learn faster but can cause oscillations, and smaller numbers will make corrections at a slower rate. Up to 3D mapping is available.

Boost Control Long Term Trim Table



This table shows the amount of Long Term correction that has been learned over time to correct for inaccurate setting of the Base Duty table. This table is user definable for axis values, however the axis channels are fixed to be the same as are used for the Closed Loop Base Duty Cycle table. This table can be adjusted by the tuner simultaneously whilst the Long Term Control is making changes. Up to 4D mapping is available.
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