We then worked on the air filters...


It appears that the original filters partially obstructs the air intake air boxes in the car thus affecting the airflow. On top of that, the OEM botom foam tends to come off and this after only 3600 miles!
photo of the original filter:

The new filters are made of foam and are thinner thus allowing optimal air flow. The flow is thus improved by 11%.

And on the dyno ?
We simply replaced the two OEM paper filters by foam filters with better design and this has led to a power gain of 6 HP and 9 Nm of torque without any further modification!



No doubt its worth it on a RS5 !