BMW S65
Encyclopedia
The S65 is a naturally aspirated DOHC 32-valve automobile
V8 engine
from BMW
.
Derived from the BMW S85
V10 engine
used in the M5
/M6
, it shares the same basic architecture and aluminium
construction. It was introduced in the E92
M3
as a replacement for the S54
straight-6
. The engine was chosen as International Engine of the Year
for the 3.0 to 4.0 L category in 2008, 2009, 2010 and 2011.
The S65B40 was developed as a result of increasingly stringent Euro V and California Air Resources Board
(CARB) emissions regulations. The S54 engine had reached the end of its development potential, making it clear a new engine was needed.
The S65 shares the same 92 mm (3.6 in) bore and 75.2 mm (3 in) stroke cylinder dimensions with the S85 V10, along with the Double-VANOS
variable valve timing
system and 12.0:1 compression ratio
.
However, the V8 does differ in a number of crucial aspects from its V10 sibling.
The VANOS system is operated from engine oil-pressure, negating the need for a separate high-pressure hydraulic system as fitted to the S85. New lightweight spark coils
with integrated knock
sensors are fitted to each cylinder, bringing the total sensor count to eight compared with two on the V10. This allows more accurate detection of knocking with the added benefit that the eight sensors actually weigh less than the previous two sensor setup.
A conventional wet-sump lubrication system with two oil pumps replaces the three-pump dry sump
system used on the V10, further decreasing weight.
The alternator
disconnects from the engine during acceleration to maximise power, only charging the battery
during braking whenever possible, in a system BMW calls Brake Energy Regeneration.
The die-cast, over-eutectic aluminium-silicon engine block is sourced from BMW's Landshut
F1
foundry, while aluminium cylinder head
s come from Hydro-Aluminium in Austria
. Other notable features of the engine include lightweight iron-coated aluminium piston
s, steel-magnesium connecting rods, forged steel crankshaft and eight throttle butterflies.
An updated version of the Siemens
MS S65 ECU
(used in the S85 V10) is fitted to the V8. Claimed to be capable of more than 200 million calculations per second, the new ECU (known as the MS S60) comfortably exceeds the 25 million calculations of which the S54's ECU was capable.
The resulting engine weighs 202 kg (445 lb): 15 kg (33 lb) lighter than the straight-6 engine it replaces, while also being shorter.
The firing order
for the S65 engine is 1-5-4-8-7-2-6-3, which is different from the typical BMW V8 firing order of 1-5-4-8-6-3-7-2
A 4.4 liter version of the engine producing 450 bhp is used in the BMW M3 GTS.
Applications:
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...
V8 engine
V8 engine
A V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
from BMW
BMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...
.
Derived from the BMW S85
BMW S85
The BMW S85B50 is a DOHC 40-valve V10 automotive piston engine present in the E60 M5 sedan, E61 M5 touring and E63/64 M6 coupé. It was derived directly from BMW's Formula 1 racing division....
V10 engine
V10 engine
A V10 engine is a V engine with 10 cylinders in two banks of five with a distinct exhaust note.- Mechanics :The V10 is essentially the result of mating two even-firing straight-5 engines together. The straight-5 engine shows first and second order rocking motion...
used in the M5
BMW M5
The first BMW M5, based on the E28 5 Series, made its debut at Amsterdam Motor Show in February 1984. It was the product of demand for an automobile with the carrying capacity of a saloon , but the overall performance of a sports car. It utilized the 535i chassis and an evolution of the engine from...
/M6
BMW M6
The BMW M6, also known as the BMW M635CSi, is a high-performance version of the 6-Series automobile, designed by the motorsport division of BMW...
, it shares the same basic architecture and aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
construction. It was introduced in the E92
BMW E90
The saloon model was the first model sold of the 5th generation BMW 3 series. Debuting in the US in 2006, the E90 came in two trims, the 325i/xi and 330i/xi models...
M3
BMW M3
The BMW M3 is a high-performance version of the BMW 3 Series, developed by BMW's in-house motorsport division, 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...
as a replacement for the S54
BMW S54B32
The S54B32 was a high-performance engine used in BMW M vehicles. The block was made from grey cast iron rather than aluminum to achieve greater rigidity from the same dimensions. It is a 3.2 L engine; bore is and stroke is...
straight-6
Straight-6
The straight-six engine or inline-six engine is a six-cylinder internal combustion engine with all six cylinders mounted in a straight line along the crankcase...
. The engine was chosen as International Engine of the Year
International Engine of the Year
The International Engine of the Year is an annual competition for automotive industry internal combustion engines, judged by a panel of automobile journalists from around the world. It is organised by the United Kingdom's largest technical motoring, aerospace and traffic management publication...
for the 3.0 to 4.0 L category in 2008, 2009, 2010 and 2011.
| Engine | Displacement | Power | Torque | Redline | Year |
|---|---|---|---|---|---|
| S65B40 | 4.0 L (3999 cc/244 in³) | 309 kW (420 PS) @ 8300 | 400 N·m (295 ft·lbf) @ 3900 | 8400 | 2007 |
The S65B40 was developed as a result of increasingly stringent Euro V and California Air Resources Board
California Air Resources Board
The California Air Resources Board, also known as CARB or ARB, is the "clean air agency" in the government of California. Established in 1967 in the Mulford-Carrell Act, combining the Bureau of Air Sanitation and the Motor Vehicle Pollution Control Board, CARB is a department within the...
(CARB) emissions regulations. The S54 engine had reached the end of its development potential, making it clear a new engine was needed.
The S65 shares the same 92 mm (3.6 in) bore and 75.2 mm (3 in) stroke cylinder dimensions with the S85 V10, along with the Double-VANOS
VANOS
VANOS is an automobile variable valve timing technology developed by BMW in close collaboration with Continental Teves. VANOS varies the timing of the valves by moving the position of the camshafts in relation to the drive gear...
variable valve timing
Variable valve timing
In internal combustion engines, variable valve timing , also known as Variable valve actuation , is a generalized term used to describe any mechanism or method that can alter the shape or timing of a valve lift event within an internal combustion engine...
system and 12.0:1 compression ratio
Compression ratio
The 'compression ratio' of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity...
.
However, the V8 does differ in a number of crucial aspects from its V10 sibling.
The VANOS system is operated from engine oil-pressure, negating the need for a separate high-pressure hydraulic system as fitted to the S85. New lightweight spark coils
Ignition coil
An ignition coil is an induction coil in an automobile's ignition system which transforms the battery's 12 volts to the thousands of volts needed to create an electric spark in the spark plugs to ignite the fuel...
with integrated knock
Engine knocking
Knocking in spark-ignition internal combustion engines occurs when combustion of the air/fuel mixture in the cylinder starts off correctly in response to ignition by the spark plug, but one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front.The...
sensors are fitted to each cylinder, bringing the total sensor count to eight compared with two on the V10. This allows more accurate detection of knocking with the added benefit that the eight sensors actually weigh less than the previous two sensor setup.
A conventional wet-sump lubrication system with two oil pumps replaces the three-pump dry sump
Dry sump
A dry sump is a lubricating motor oil management method for four-stroke and large two-stroke piston internal combustion engines that uses external pumps and a secondary external reservoir for oil, as compared to a conventional wet sump system....
system used on the V10, further decreasing weight.
The alternator
Alternator
An alternator is an electromechanical device that converts mechanical energy to electrical energy in the form of alternating current.Most alternators use a rotating magnetic field but linear alternators are occasionally used...
disconnects from the engine during acceleration to maximise power, only charging the battery
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
during braking whenever possible, in a system BMW calls Brake Energy Regeneration.
The die-cast, over-eutectic aluminium-silicon engine block is sourced from BMW's Landshut
Landshut
Landshut is a city in Bavaria in the south-east of Germany, belonging to both Eastern and Southern Bavaria. Situated on the banks of the River Isar, Landshut is the capital of Lower Bavaria, one of the seven administrative regions of the Free State of Bavaria. It is also the seat of the...
F1
Formula One
Formula One, also known as Formula 1 or F1 and referred to officially as the FIA Formula One World Championship, is the highest class of single seater auto racing sanctioned by the Fédération Internationale de l'Automobile . The "formula" designation in the name refers to a set of rules with which...
foundry, while aluminium cylinder head
Cylinder head
In an internal combustion engine, the cylinder head sits above the cylinders on top of the cylinder block. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by a head gasket...
s come from Hydro-Aluminium in Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
. Other notable features of the engine include lightweight iron-coated aluminium piston
Piston
A piston is a component of reciprocating engines, reciprocating pumps, gas compressors and pneumatic cylinders, among other similar mechanisms. It is the moving component that is contained by a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from...
s, steel-magnesium connecting rods, forged steel crankshaft and eight throttle butterflies.
An updated version of the Siemens
Siemens AG
Siemens AG is a German multinational conglomerate company headquartered in Munich, Germany. It is the largest Europe-based electronics and electrical engineering company....
MS S65 ECU
Engine Control Unit
An engine control unit is a type of electronic control unit that determines the amount of fuel, ignition timing and other parameters an internal combustion engine needs to keep running...
(used in the S85 V10) is fitted to the V8. Claimed to be capable of more than 200 million calculations per second, the new ECU (known as the MS S60) comfortably exceeds the 25 million calculations of which the S54's ECU was capable.
The resulting engine weighs 202 kg (445 lb): 15 kg (33 lb) lighter than the straight-6 engine it replaces, while also being shorter.
The firing order
Firing order
The firing order is the sequence of power delivery of each cylinder in a multi-cylinder reciprocating engine.This is achieved by sparking of the spark plugs in a gasoline engine in the correct order, or by the sequence of fuel injection in a Diesel engine...
for the S65 engine is 1-5-4-8-7-2-6-3, which is different from the typical BMW V8 firing order of 1-5-4-8-6-3-7-2
A 4.4 liter version of the engine producing 450 bhp is used in the BMW M3 GTS.
Applications:
- 2008–present E90, E92, E93BMW E90The saloon model was the first model sold of the 5th generation BMW 3 series. Debuting in the US in 2006, the E90 came in two trims, the 325i/xi and 330i/xi models...
M3BMW M3The BMW M3 is a high-performance version of the BMW 3 Series, developed by BMW's in-house motorsport division, 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... - 2009–present Wiesmann Roadster MF4-SWiesmannWiesmann is an automobile manufacturer in Germany. The company was founded in 1985 by the brothers Martin Wiesmann and Friedhelm Wiesmann . The cars are manufactured by hand in Dülmen...
- 2010–present Wiesmann GT MF4-SWiesmannWiesmann is an automobile manufacturer in Germany. The company was founded in 1985 by the brothers Martin Wiesmann and Friedhelm Wiesmann . The cars are manufactured by hand in Dülmen...