There is no direct replacement for the S65, since the following generation of M3 switched to a turbocharged straight-six engine (the BMW S55).

Derived from the BMW S85 V10 engine (as used in the E60 M5), the S65 shares the same basic architecture and aluminium construction.

Other common features include individual throttle bodies,[3] ionic current knock sensing,[4] double-VANOS (variable valve timing) and the 12.0:1 compression ratio.

To reduce weight, a wet-sump lubrication system with two electrically operated scavenging pumps and a main oil pump replaces the three-pump wet-sump system used on the S85.

Applications: The S65B44 is an enlarged version of the S65, due to a larger stroke of 82 mm (3.23 in).