The American tool that helps make BMW's in-line six engines so good

You can argue the merits of V12s, V10s, V8s, V6s, and boxer engines all you like, but the most harmonised and perfect engine configuration is in the in-line six.

And it has nothing to do with numerology and everything to do with physics.

Powerful, with an inherent balance impossible to engineer into other engine configurations, in-line sixes are the choice for those drivers who value the perfect blend of smoothness and power.