BMW S85


The BMW S85 is a naturally aspirated V10 petrol engine which replaced the BMW S62 V8 engine in the M5 model and was produced from 2005–2010. It was both BMW's first and only production V10 engine, and the first petrol V10 engine to be available in a production sedan.
Introduced in the E60 M5, the S85 was inspired by BMW's previous Formula One involvement. Unlike most other BMW M engines, the S85 is not related to a regular production BMW engine.
The BMW S65 V8 engine is based on the S85.

Nomenclature

As the S85 was BMW's first V10 engine, it was given a new series in the BMW's engine codes. The "60s" were used for V8 engines and the "70s" were used for V12 engines, therefore the V10 was allocated in the "80s" (despite having fewer cylinders than the V12 engines in the "70s".
The engine code for the related BMW S65 V8 engine reflects its link to the S85. The S65 code was selected to signify that the V8 is largely derived from the S85 minus two cylinders, and not related to BMW's other V8s.

Design

The S85 has dual overhead camshafts with four valves per cylinder and double-VANOS. The engine block and cylinder head are constructed from aluminum alloy.
Peak power is at 7,750 rpm and peak torque is at 6,100 rpm.
The redline is 8,250 rpm, and the specific output of per litre is amongst the highest of naturally aspirated production car engines.
Features include:
The S85 has won the following awards at the International Engine of the Year: