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Old 07-09-2013, 09:27 PM   #25
mid_life_crisis
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Quote:
Originally Posted by jamesm View Post
You don't need any of that. Way too complicated. You don't need to know how fast the motor is spinning to control boost. All you need to know is what the target is at any given time and what your current value is relative to it. A wastegate doesn't know anything about the turbo it is controlling. It only knows what it's spring pressure is and what it's boost reference is relative to it (mechanically speaking, but you get the point).
The three dimensional reference table gives us the ability to have different boost targets based on the combination of rpm and throttle position. This is far more versatile than just a simple loop keeping the boost stable relative to throttle position or rpm.
It could be done without the motor speed but I wanted it for a reason that eludes me now.
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