BMW premieres "M-Ignite" pre-chamber technology for the M2, M3 and M4

As efficiency and emissions legislations get ever tighter manufactures are forced to come up with innovative solutions, and BMW have just shown off their latest one, dubbed “M Ignite”. M Ignite uses a pre chamber to reduce the chance of knocking and make the combustion more efficient.

The system still has a conventional ignition system, now mounted off to the side of the combustion chamber, however in the top of the cylinder head there is a secondary chamber with small openings, that allow the air fuel mixture to be forced into the chamber under compression. At the top of the chamber is a second sparkplug that ignites the mixture in the pre-chamber, which forces the flame out of the openings into the main combustion chamber, causing a higher combustion rate.

The normal spark plug is still used primarily in lower load and lower RPM applications, with the chambered sparkplug firing sequentially, in a similar fashion to Alfa Romeo’s Twin Spark engines of the 1990s. At Higher RPM and load conditions the pre-chamber takes over.

BMW says this will reduce exhaust gas temperature and reduce the likelihood of knocking. BMW taking advantage of this by increasing the compression ratio on the revised S58, as well as fitting it with variable turbine turbos.

M3s and M4s from July of this year will come with the revised S58, and the M2 will get the engine in august

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