No Bov?


General of the Army
Oct 18, 2016
2009 E93 335i
So the B58 has no BOV/DV and uses a combination of things to avoid this:
Blow-off valve
A blow-off valve is not used in current models. Pressure peaks, caused by sudden load shedding due to the inertia of the turbine of the exhaust turbocharger, can be avoided by careful tuning of the Digital Motor Electronics software. With foresighted charging pressure control, pressure peaks can be predicted and reduced by quick adjustment of the electrically-adjustable wastegate valve. Assisted by a delayed load control of the Valvetronic (in the minimum lift direction) or the throttle valve (in the closed direction), the remaining charge air which is produced can be routed to the exhaust emission system via the engine. This form of control thus prevents the exhaust turbocharger shaft from being exposed to excessive torsional stress due to high pressure peaks.

This makes me wonder how this balancing act can be maintained after moderate to heavy modification. Combined with the no/little vacuum aspect of the Valvetronic and electronic wastegates, it seems there is a little bit of engine tech to catch up on.

If I recall, the EWG was done midway through the N55, it looks like the N54 will be the last engine with these functions.


Jun 5, 2017
07 335i MT
N63R is like this too I believe that all make an extremely unique burble between shifting its pretty bad ass sounding!