Originally Posted by RGRAY
2. "how many of us could feel the 13 bhp" Well it seems like matsarge and all the people who posted an the 5 series forum did.
I believe they all have said the car runs smoother too.
If you go to the length of taking out that filter, your subconsciousness will make pretty damn sure you will feel the car runs smoother and has more power afterwards. If thatīs enough for you, fine and stop reading this post.
Only a true double blind test is valid in determining the usefullness of a modification. And whenever that scientific principle is applied (it rarely ever is), claims of free power and smoother running ALLWAYS falter. Just like with astrology and homeopathy...
"feeling" 13hp on a 510hp M5 is plain riddiculous. It would not even be measurable except on a static engine only dyno (not a wheel dyno, on wheel dynos the tollerances would be too high).