OK, so I've done some more digging on the air filter issue, and I did find the GruppeM RAM AIR SYSTEM. It would cost me around 500 euros, which is OK if it provides the modest HP improvement when coupled with the RPi scoop and also a better engine sound.
If I understand correctly the GruppeM RAM AIR SYSTEM replaces the OEM air filter and box, and RPi scoop forces more air to the RAM AIR SYSTEM. Are these assumptions correct? (I am not an expert, YET
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