BMW M3 Powered By A Mazda Four Rotor Engine

The BMW M3 is a high-performance version the BMW 3 Series, developed by BMW's tuning branch BMW M. M3 models have been derived from the E30, E36, E46 and E90/E92/E93 3-series, and sold with coupé, sedan and convertible body styles. Common upgrades over the "standard" 3-Series automobiles include more powerful and responsive (yet at times smaller) engines, improved handling/suspension/braking systems, more aggressive aerodynamics/body, and multiple interior/exterior accents with the famed tri-color "M" (Motorsport) emblem.
The Mazda Wankel engines (a type rotary combustion engine) are family car engines derived from experiments in the early 1960s by Felix Wankel, a German engineer. Over the years, displacement has been increased and turbocharging has been added.
Wankel engines can be classified by their geometric size in terms radius (rotor center to tip distance, also the median stator radius) and depth (rotor thickness), and fset (crank throw, eccentricity, also 1/4 the difference between stator's major and minor axes). These metrics function similarly to the bore and stroke measurements a piston engine. Displacement is 3√3radius·fset·depth, multiplied with the number rotors (note that this only counts a single face each rotor as the entire rotor's displacement). Nearly all Mazda production Wankel engines share a single rotor radius, 105 mm (4.1 in), with a 15 mm (0.6 in) crankshaft fset. The only engine to diverge from this formula was the rare 13A, which used a 120 mm (4.7 in) rotor radius and 17.5 mm (0.7 in) crankshaft fset.