An evolution of the M113 V8,[1] all M273s have aluminium engine blocks, sequential port fuel injection, fracture-split forged steel connecting rods, a one-piece cast crankshaft, and a magnesium intake manifold.

The cylinders are lined with silicon/aluminium, and a dual-length variable-length intake manifold is fitted.

[2] In addition to this, new features shared with the M272 include DOHC aluminium cylinder heads, 4 valves per cylinder and independent continuously variable valve timing on both the intake and exhaust sides.

A new electronically controlled cooling system has eliminated the need for a mechanical thermostat for improved engine warm-up and optimum control of engine temperature.

Applications: *Note: 500 or 550 model naming varies depending on geographical market.