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[http://volvospeed.com/vs_forum/topic/159506-tuners-rejoice-free-tuning-for-m44/?do=findComment&comment=2325987 refer to discussion on page 233]
 
[http://volvospeed.com/vs_forum/topic/159506-tuners-rejoice-free-tuning-for-m44/?do=findComment&comment=2325987 refer to discussion on page 233]
 
'''LDR P-part only hack:''' modified LDR control routine locks I-part (integrator of the PID logic) at zero to prevent silly under/overshoot of the boost control duty cycle value, This also prevents the P-part (proportional component of the PID logic) from going positive, only allowing negative correction.
 
 
To set this up, set up your duty cycle map as you like it, do some data logging, then build the target load map to match the curve of your duty cycle map. Then, if load exceeds the target, say because it's winter and the air is now denser or whatever running condition you have generates more load than you expect, the duty cycle will be reduced somewhat to target the load setpoint. So, in essence the target load map turns into a (loose) "max load" map, and the system runs fully off the duty cycle map unless target load is exceeded.
 
 
Note that without the integrator, the correction range of the proportional component is fairly limited, so don't expect it to prevent large amounts of boost overshoot, but it will help you build a map combination that results in fairly stable target load without all the nastiness of boost over/undershoot due to the rudimentary integrator logic.
 
 
Table PLDRN "LDR P-part" defines the amount of correction based on RPM range: higher values in that table cause the P-part to deviate more for a given system deviation (difference between actual and max load). Increase for more aggressive correction, decrease for less aggressive correction. Toying with the duty cycle, max load, and PLDRN maps will be neccessary...
 
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