The rumor that BMW will soon reveal a smaller, lighter, triple-turbocharged X3 M is very exciting. The three turbos are speculated to enable the car to deliver up to 449hp. The three turbos will be piped into a tweaked variant of BMW's straight-six, which probably means that it will get a 3.2-liter displacement. The report from CAR states that the three-turbo setup will feature one electric turbo and two of the usual type, according to MotorAuthority.
Typically, electric forced-induction setups are used to provide low levels of boost pressure at idle and very low rpms since they don’t rely on engine speed or exhaust flow.
It will probably give a boost that’s on the baseline level with only minimal losses.
This allows the use of bigger primary turbos without any turbo lag. This same engine is also expected to be used on the next-gen M3.
[via - 4wheelsnews]2011 Bmw X3 M Pack
