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      03-17-2020, 03:24 PM   #33
Nezil
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Drives: LCI '18 6MT M2
Join Date: Jul 2017
Location: San Francisco Bay Area

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Quote:
Originally Posted by SeanWRT View Post
Hi Nezil, noticed you updated days ago, but didn't have time for a second look at log until now.

The WG behavior does seem abnormal. As when pedal fully back on, the boost delta is big enough to warrant a 100% WG duty but it held back a little to 80%.

Has it been consistently that way?

I suspect the safety action was still being taken at that moment, if the unsettling RPM is any indication. It could be the clutch not being fully engaged or the uneven road surface (less likely as I know what log would've been like).

WG is 100% for a short time (when RPM settles) before it goes down to 80% again which is normal - when boost is close enough to target, WG% goes down to prevent from overshoot, something you can find out for yourself if you floor it off boost and from low rpm.

Please take a look from other logs, specifically at WG behavior after 100% pedal.
Always thanks to you SeanWRT, for taking the time to respond. I've been busy myself and now only find the time to respond.

First off, I'm really glad and encouraged that you can see the WG behaviour seeming to be abnormal. To answer your question... Yes, it has always been that way, every single time I shift. Stock and tuned, with and without FBO parts.

The unsettling RPM is probably clutch shudder as it re-engages, particularly 1st to 2nd or 2nd to 3rd shifts, I can do logs of 3rd to 4th pretty easily and you'll see less of it there, but the same WG behaviour; I don't think they're related. The WG delay is always and consistently exactly 1 second; it really does look suspiciously like a software thing.

I'll try to gather some more logs, but this WG behaviour is consistent for my car. One thing I'd like to try is letting of the gas, and dipping the clutch but not shifting. This should indicate if the WG behaviour is linked to the clutch signal, as I suspect.

widetyres suggests that Porsches had a similar behaviour in the past?
Quote:
In the end, I'm positive 100% WG won't solve the problem with 1.4s shift...Key is still off pedal time. As you see from DCT log, the system is able to hold boost during shift and for most of the time is dealing with overboost.
Of course. I can capture a log with a quicker shift, but I am certain it won't be different. I'm not expecting DCT performance at all, and I totally expect 6MT to be compromised in performance for that reason.

The WG closing properly should reduce the total lag down to true turbo lag, which is fine, and only what I'm trying to achieve.
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