BMW S85 V10 Engine
From 2005 to 2010
|Configuration||90° V10, odd-firing|
|Cylinder bore||92 mm|
|Piston stroke||75.2 mm|
|Cylinder block alloy||Aluminum–silicon alloy|
|Cylinder head alloy||Aluminum alloy|
|Fuel system||Fuel injection|
|Management||Siemens MS S65 ECU|
The BMW S85B50 is a DOHC V10 piston engine which replaced the S62 and was produced from 2005-2010. Used in the E60 M5 sedan, E61 M5 touring and E63/64 M6 coupé, it was inspired by BMW's previous Formula 1 involvement.
As the S85 was BMW's first V10 engine, it was given a new series in the nomenclature. While V8 engines are designated by "60s" and V12 engines labeled as "70s", the S85 was badged with an "80" despite it having fewer cylinders than the "70"-series engines.
The S85 spawned a related S65 V8 engine for the 2008 BMW M3. Although the "65" designation is apparently out of order compared to the other V8 engines (which follow "62" and "63" sequentially), the S65 was badged such since its design is largely derived from the S85 minus two cylinders, and not related to BMW's other V8s.
Unlike other BMW engines, there are no mass market "M" or "N" versions of the S85 and S65 and nor are there any shared parts, as these engines are used exclusively in BMW M performance vehicles.
BMW 6-Series M6 (2005 - 2010) 5.0 V10 engine specs
|Top Speed||155 mph|
|0-60 mph||4.5 secs|
|Torque||520 Nm, 384 ft-lb|
|CO2 Emissions||342 g/km|
|Euro Emissions Standard||4|
|Miles Per Tank||292 miles|
The S85B50 is a high-revving engine designed to utilize power from a wide rev band. Having a redline of 8250 rpm, it achieves over 100 bhp (70 kW)/litre. The S85 features a very high compression ratio of 12.0:1, exceeding the previous S54's ratio of 11.5:1.
It produces over 100 hp more than the previous E39 4.9liter V8, whilst weighing only 2.2 pounds more. The S85 utilizes both individual throttle bodies and Double VANOS (BMW's infinitely variable timing for intake and exhaust cams.
|Power output||373 kilowatts (500 hp)|
|Torque output||520 N·m (384 lb·ft)|
|Dry weight||240 kg (529 lb)|
- 5.0 Litre V10 engine, 90 degree bank angle, 507 hp (378 kW) @ 7750rpm/520 N·m (384 lb·ft) torque @ 6100rpm
- Cast aluminum block with bed plate design split at the crankshaft axis.
- Cast aluminum heads with four valves per cylinder and CNC machined ports and combustion chambers. Valves are actuated through non-rotating inverted bucket cam followers.
- Oil-cooled, forged aluminum pistons from Mahle Motorsport
- Forged steel crankshaft with counterweights, shared crankpins producing an uneven firing interval of 90 or 54 degrees.
- Double VANOS system which varies both intake and exhaust cam phasing
- 10 individual electronically controlled throttle butterflies
- Knock sensors have been eliminated by utilizing the "ionic current" measuring system. Using the ionic current system, engine misfires as well as knock can be measured simultaneously. The ionic current is measured by passing a low voltage across the spark plugs immediately following the ignition spark. NGK supplies this specific dual purpose spark plug (model: LKR8AP) and there are no compatible equivalents from other spark plug manufacturers.
- Quasi-dry sump lubricating system
- The firing order for the S85 engine is 1-6-5-10-2-7-3-8-4-9.