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      03-06-2020, 02:16 PM   #9
Nezil
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Drives: LCI '18 6MT M2
Join Date: Jul 2017
Location: San Francisco Bay Area

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Thank you so much for stepping in @SeanWRT, I know you're a master of interpreting logs.
Quote:
Originally Posted by SeanWRT View Post
WG% does not indicate lag. It simply means how much exhaust flow is needed to quickly build boost to target or stay on target. When it shows 100%, you're off boost that's all.

For example, a laggy big turbo car, floor it. WG instantly open to 100% and stay there for like 5-6 sec, before anything happen.
Yes, I understand this, but I think you've missed my point. I can feel that the car is off boost immediately following a shift, but at that point, WGDC is not at 100%, it's quite a bit lower. After about 0.1s it seems to behave normally, hitting 100% until boost target is reached and then dropping to control it.
Quote:
The channels you really need to look at, are 1) pedal input %, 2) torque request, 3) load target and 4) MAP.

Pedal input is driver's intention.
Torque request is how ECU react to your input.
Load target is the calculated load that's actually going on, not the target of load literally.
MAP is the actual boost the cylinders are seeing.

If you monitor above channels closely, I believe you're smart enough to figure out where the lag comes from...
I don't have Torque request logging currently, but will turn it on for future runs. The chart below is the same data capture as my first post in this thread, but with Accel. Pedal now shown, along with MAP rather than Boost (Pre-Throttle). You can clearly see that once I get back on the gas after the shift, there is a delay before the Load Target and MAP rise up, and it seems to be caused by the WGDC not hitting 100%.


From what you've said, it looks like the Torque request might be the missing piece of the puzzle, and if this truly is causing this 'lag', then it's a software issue that could be potentially improved... Can you think of any reason why the DME isn't allowing boost to build correctly for 1 second after a shift in 6MT?
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Last edited by Nezil; 03-13-2020 at 12:41 AM..
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