I thought I knew what I was doing but apparently not so here I am asking for help. Two questions:
Why does the boost duty cycle not follow the table unless you have PID active? Shouldn’t it just be following it exactly as an “open loop” type control? This is shown in 4.0Trying and noresponse log. Happens though the entire log, but is most noticeable at 1:13
in the 3.9Boost and Boost log, why is the duty cycle following the table perfectly, and then suddenly slamming shut, causing me to spool and over boost? Happens at 8:36
Mind you, 10 is wastegate full closed and 66 is full open in regards to duty cycle.
Ok I just noticed something, The boost DC drops to 10 when the margin above target is exceeded. and then when it is back within the range it goes back to DC feedback table value before once again exceeding the upper margin and defaulting to DC of 10. Is the software assuming that a lower DC is to open the wastegate to bring the boost level back down? and if so, do I simply need to invert the output, and invert all my tables to reflect lower DC = less boost? because as it is right now, less duty cycle is more boost.
Last night I inverted the output in parameters and inverted the values in the DC feedback table so that 88% is full closed and 48% is full open. Did a few pulls and had large oscillations in boost at the top end, but wasn’t hitting fuel cut or over boosting. I guess that was the issue. I’ll refine the PID and margins today to see if I can get it to hold steady.
I have a few requests if it’s not too much. I know it may seem stupid but I checked the help menus and it doesn’t say anywhere that more DC = more boost and less DC = less boost. Would it be possible to make a note of that in the help menu, maybe in the DC feedback table or something. That way others who are relying on the help menu like myself can know that the DC corrections are coded in the software to only correct in that one specific way.
Second, as stated, I’m using an EWG controlled by a Full race controller. The controller accepts a PWM DC that a typical boost control solenoid would accept. However, their instructions call for a signal of 1khz. Would it be possible to either set the max PWM frequency to 1khz, or under EWG, allow for another option like “controller” with a selectable output, sinse in that menu you can set the frequency to 1khz.
In the fewest words possible: because that’s what it wanted
If you noticed in my first post my min an max DC are offset, 10 - 66. meaning everything above 66 is out of range (no longer moving the wastegate because its maxed out.) 10 was at the max clamping pressure (closed) without exceeding the voltage spec set in the full race wastegate calibration proceedure.
When I invert the output, those windows shift and have to be compensated for.
I’m probably explaining this very poorly, it’s easier if you see it, but basically all I did was invert the output, and then I recalibrated the wastegate by manually sweeping the duty cycle with the DC lock and visually watching what DC correlated to how much it was open, and those are the numbers I got.