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Title: Boost spikes after gear change (wot acceleration) / LDR Q2? Post by: TeknoFi on July 20, 2023, 02:21:40 AM Hi,
the problem I have is that I've got the boost pressure spikes, when changing gears. Even after adjusting the kfldimx but it's not enough. The higher the revs end up after the change, the bigger the spike. what would be the orthodox solution to this. LDR Q2? How should it be exactly adjusted? Just more and more, until spikes are gone? Or is there other effective solutions than Q2? I have raised but not very much benefit with big rpms, at least with moderate rise of the first two rows (100 and 200) at the point where the spikes occur. Also why does the wg dc jump to 100 during gear changes (clutch pressed) at high revs, how could it be reduced if it is partly to blame? This is 1.8T AJQ, only de-cat, 2,5" dp, and basic "stage1" tune. In logs, where peaks are shown, they came with LDR Q2 adjusted like in that screenshot. Title: Re: Boost spikes after gear change (wot acceleration) / LDR Q2? Post by: terminator on July 24, 2023, 09:45:51 AM The torbocharger made in China?
Title: Re: Boost spikes after gear change (wot acceleration) / LDR Q2? Post by: celtempperformance on July 25, 2023, 03:38:10 AM You can try set: CWMDAPP on 8 and work with boostmap KFLDRAPP to see if it makes any differents.
Title: Re: Boost spikes after gear change (wot acceleration) / LDR Q2? Post by: nyet on July 26, 2023, 01:00:48 AM You didn't log a single PID variable.
That's going to make it hard to diagnose. If I had to guess, though, your IMX is too high. Title: Re: Boost spikes after gear change (wot acceleration) / LDR Q2? Post by: nyet on July 26, 2023, 02:35:43 AM The hints are these WGDC overshoots. When Q2 and Q0 are zero (p and d), the only remaining contributor is Q1 (i). If IMX is too high, after overshoot, the WG will settle on the imax value (since i is wound up during spool).
Title: Re: Boost spikes after gear change (wot acceleration) / LDR Q2? Post by: TeknoFi on August 05, 2023, 12:11:25 PM Hello again.
From one issue to another. Now there is crazy oscillation above 3700rpm. feels like riding with horse. and it looks like its n75 induced because in logs it throws between 60-100% i dropped q2 but it doesn't help, i'm confused what could be causing this? Title: Re: Boost spikes after gear change (wot acceleration) / LDR Q2? Post by: TeknoFi on August 26, 2023, 01:35:35 PM Solved by damping Q2 (to get rid of oscillation) and playing shaving game with KFLDRL (to get rid of boost peaks). Last 3 rows after 3000rpm to value which produces ~1bar boost without spiking. I know downsides but at this point they dont matter, as this works good.
kfldimx numbing didn't help because wgdc peaked up to a hundred every time I changed gears and actually that caused a spike, not so much exact kfldimx value. Well then ldr q2 would have been the solution? was not due to the problem mentioned above. Strange thing but now its good, and thanks for the participated. |