Originally Posted by KIYO
I think it is controlled by some formula.
I am monitoring the engine load and the RPM.
I found out that if the engine load is low, it doesn't get louder at around 2500RPM.
This is a good point. So it does not just depend on RPM, but also which gear you are in and the speed in which you are traveling at...
I wonder what the loss/ gains would be to going catless or secondary catless. I am very tempted, I just do not know enough to make the educated decision. Will I lose power? Would I gain power? Is it more complicated than that? Does BMW have a special formula to make the cats work in junction with everything else? What is truth in this matter?