I have an E92 and the wife an E83. Both have the N52 engine (N52B30 to be exact)....but each is tuned slightly different.
My E92 has a rated 230 HP while the E83 is rated at 260 HP IIRC...
Having both in my garage, I can say the E83 is very much more responsive.. Not much more powerful, but definitely more throttle responsiveness. That implies (at least to me) that there is a way to "tune" the E92?? Maybe this is what installing a JB would give me??
From a Wiki I also saw the statement below which may explain it straight away:
*output changes result from the omission of the variable resonance system, dual plenum intake runner system, and the variable back pressure muffler.
Any other thoughts for me to brew on?
('07 E92 328xi / '08 E83 X3)