Is red actual and green desired boost? Your actual boost is all the time lower than desired boost. you didn't set up n75 map properly. Did you have log with actual, desired bost, n75 vanes %, overboost strategy, fuel, and intake air? What i see, and i can't see much from this, your pid controler cant realign boost...

YEs..my PID or something is fucking me up...i can give you details...i really make tuning for a lost of cars and know all theorey.
But on my car this shit is embarassing me...maybe sticky vanes?
main idea is that i request 2300..and goes to 2450+ ...i longered turbo rod..opened n75 too much for this..

do a slow acceleration from 1500 to 4500rpm in 3th gear, and one acceleration from 1500 to 4500 rpm at wot. If you have spikes in slow acceleration same as wot than you didn't adjust turbo rod and n75 map properly. You didn't have to touch turbo rod, only n75. Now it be hard to adjust all properly

I dont have spikes when i accelerate slow and light..just when push pedal brutal to max.

n75 map are problem than, or turbo vanes, but if you have t. spikes on 2500rpm, open turbo vanes more from 2000rpm, than do a log. if turbo vanes are slow, if you open vanes from 2000rpm it will have more time to open. if you have turbo spike again on the same rpm you have another problem

:o ok thanks

DavidRUCABITS wrote:The correct order should be:

Requested
Limiter
Svbl

SVBL is the safety for your boost tune, turbos with stuck geometries will spike or over-boost. SBVL is there so that if something goes out of what you tune it will stop everything and the car enters in limp mode (Safe).

Hope it help

I have a question here. yo say that more than SVBL goes in limp mode..but as i know only with 300 or 400 mbar more than svbl will go in limp mode. Then its a good idea to increase it ? Because mauybe my map sensor cant read more than 2500 mbar.

If you pass the map sensor capability you will limp. If you pass SVBL it will limp.

SVBL is the ultimate security for your turbo, if you search for the part number of your MAP sensor you will see the max value allowable.

Regular Map sensor will reach 3Bar (Atm + boost) so they are good for boosting 2Bar +-, a boost spike will limp. Set your SVBL 150mbar above the requested boost.

Take a good look at you compressor map and see if you can boost 1,5bar all the way... when does it limp?

In a (bad) tune that i did in the beginning of my tune journey i put mine gt1749Va boosting 1,5 bar until 5000rpm...lol :roll:

Didn't blow just for luck... with 180k is still doing is job, now boosting 1,5 @2500 and decreasing until 4900rpm.

You lucky right ;)
For example my turbo compressor map is up to 2500 mbar, maximum maximum limit.
I request 2300 from 2250 rpm to 3800 , after that i lower pressure to 2280(4000) , 2250 - and so on.
Limiters are set to 2400, both of them
BMw original maps are : requested 2100 from 2000 to 4500 , and limiters both to 2250. Limiters are the same..maybe PID controller is better than on other cars.
Also i saw on 320d 150 hp version than requested is 2400 mbar, and both limiters are the same 2400..no more than 2400..and works awesome..that is edc16 and i think that PID is better

Hello. I may be a bit off topic here, and I'm also a bit noob on tuning yet, but I know control engineering since this is my background. Isn't it possible to change the PID controller gains (Kp, Kd, Ki) to fine tune it a bit in order for you to get a faster/less overshoot response?
I don't really know if one has access to this info in the .bin file, at least if is not a full read, but I built a controller some time ago to control my new VNT turbo (with electric actuator) and one of the things that would influence really hard the response would be to change the proportional and derivative gains on my PID (not so much the integral gain)...
Also, does anyone know for sure what kind of boost control strategy this cars have? I mean, we always have a setpoint boost (desired boost) map and the N75 map, which is a bit contradictory because if you set the "position" of the vanes by "forcing" some N75 %, then you shouldn't be able to do "close loop" control to achieve the desired boost. So somehow the ECU must decide when to change from "open loop" to "close loop" (PID) control right? I'm sorry if this is covered elsewhere, I can't seem to find it, at least yet!
Thanks!