Thanks nyet. I think I may have discovered the error in my ways. I'd been setting a smooth LDRXN and getting too tied up with making it look smooth when really that was my problem, I've now messed with LDRXN and upped it where i had the dip in requested boost between 3 and 4k which IMO made it really hard to control, and I could feel the drop in torque when driving which wasn't nice.

Now my LDRXN is changed my requested boost looks a lot better and i hope will be easier for me to control without any fluctuations in boost.

Pulling a fair amount from IMX did result in a massively reduced overshoot, i hope with my fixed LDRXN and nicer desired boost that with some mods to IMX i'll have it exactly how I want it. Will update when I get it sorted as it might save some other noobs some time 

yea a bit too low.

You'll never be able to tune out all of the wobble.

Yes it is.

Notice how your I-MAX is smooth, but your WGDC is all over the place?  What does your KFLDRL look like?  Pay less attention to your actual boost, and pay more attention to the WGDC.  You want to make that smooth instead of jagged like it is now, and the boost will even out as well.

You could also look at boost pid trims to see how the ECU is trying to compensate, and apply those trim adjustments to DIMX, in the same manner that you would tune KRKTE based on partial LTFTs.

Yes, positive trims = increase, negative = decrease.  Look at STLDIA1-4 to determine the rpm ranges.  Look at the S4 wiki's I-Regulation adaptation section for more details on this

At first, ignore the overshoot, and try to get boost stable with DIMX.  Once you are good, increase Q2 in the areas needed to prevent overshoot on ramp up.   To aid in keeping boost a little more stable on initial ramp up, you could slightly decrease values in the 95% column from ~3,000 to ~4,500rpm.

Did you do anything with D term (Q2)?  Looks like too much. 

Thanks SB_GLI , I'll put that into practise soon. I think I'll raise my IMX up a fair bit to get me closer to desired boost ignoring the overshoot so my WGDC isn't flapping around all over the place. Then I'll report back hopefully with some decent results.

I have not yet touched any of the PID maps, the only thing I've messed with is IMX up until now. I'm just feeling like whatever I've done so far hasn't really got me much closer to getting it right lol however I never wanted to mess with the PID maps if it could all be sorted with IMX. I've done that many revisions with IMX at different settings and can't seem to get it right 


Nyet, by this do you mean i should be making some changes to my LDRXN lifting it way above actual boost on spool to the point where on my logs my requested boost looks like a horizontal line (obviously then tapering down as revs increase and turbo can't keep up)

Made some adjustments to IMX but it's still not right. Seems like whatever I do with IMX I end up with that dip in boost around 3500rpm. I've tweaked IMX so many times and can never get it anywhere near being right

I've tried to make the boost request flat on spool as nyet suggested, not sure if what I've done is actually what is required or not though.

Is this dip in boost around 3500rpm the PID almost over correcting the over shoot? or is it because my IMX is too low in that area?
As if its the PID correcting the overshoot then I should decrease IMX to stop the overshoot, but if its because imx is too low then I guess I need to increase those areas of IMX?

Also I don't seem to be getting that many boost PID corrections in the are where I'm having all the problems