Serious performance problem

Hello



I own 325i steptronic, well maintained. In past year i replaced camshaft sensors, installed Schmiedmann headers, new o2 sensors. DISA is ok, MAF looks ok too, no error codes. Car feels strong up to 140kmh so i had no idea that im SLOW. Utterly slow. You can feel torque and "grunt" but once i measured 100-180...i was very dissapointed.



I was comparing this time to another 325 owners (youtube videos) and most of them have 100-180 in 15-16s. My car is doing same in 25-26s



Im literally out of ideas. Compression test shows 12/12/12/12/12/12 so i think engine is OK. I think that there are few potential causes.



1. MAF

2. Transmission (it works fine btw, smooth shifting even in winter etc)

3. Fuel filter



But again, i have no errors stored in DME. My fuel trims stft/ltft are almost zero :hmm:



Any ideas ? I cant even hit 200km.


My car :

http://ift.tt/1Gt5irl



Reference car :

http://ift.tt/1F7Mwsu