| BMW S65 Engine | |
|---|---|
.jpg) S65B40 in a E93 M3 | |
| Overview | |
| Manufacturer |  BMW |
| Production | 2007–2013 |
| Layout | |
| Configuration | 90°V8 |
| Displacement | 4.0 L (3,999 cc) 4.4 L (4,361 cc) |
| Cylinder bore | 92 mm (3.62 in) |
| Piston stroke | 75.2 mm (2.96 in) 82 mm (3.2 in) |
| Cylinder block material | Aluminium |
| Cylinder head material | Aluminium |
| Valvetrain | DOHC w/VVT |
| Combustion | |
| Fuel system | Electronic multi-point fuel injection |
| Fuel type | Petrol |
| Oil system | Wet sump |
| Chronology | |
| Predecessor | BMW S62 |
| Successor | BMW S63 |
TheBMW S65 is anaturally aspirated V8 petrol engine which was produced from 2007 to 2013. Its main use was in theBMW M3 (where it replaced theBMW S54 straight-six engine). There is no direct replacement for the S65, since the following generation of M3 switched to a turbocharged straight-six engine (theBMW S55).
Derived from theBMW S85 V10 engine (as used in theE60 M5), the S65 shares the same basic architecture and aluminium construction. Unlike most otherBMW M engines, the S65 and S85 are not related to a regular production BMW engine.[1]
The S65 won theInternational Engine of the Year award for the 3.0 to 4.0 L category in 2008, 2009, 2010, 2011 and 2012.[2]
The S65 shares the same cylinder dimensions with the S85 V10, with a 92 mm (3.6 in) bore and a 75.2 mm (3.0 in) stroke. Other common features include individualthrottle bodies,[3] ionic currentknock sensing,[4]double-VANOS (variable valve timing) and the 12.0:1compression ratio.[5] The redline is 8,400 rpm.
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.[6][7][8] The dry weight of the S65 is 202 kg (445 lb).[9]
Thealternator reduces or stops charging (depending on battery charge level) during acceleration to maximise power, only fully charging the battery during braking and decelerating whenever possible, in a system BMW calls Brake Energy Regeneration.[6]
Theengine control unit (ECU/DME) is aSiemens MSS60,[10][11] which is based on the Siemens MSS65 ECU used in the S85 engine[12]The S65 weighs 202 kg (445 lb), which is 15 kg (33 lb) less than itsS54 straight-6 engine predecessor.[13]
Thefiring 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.[14]
| Engine | Displacement | Power | Torque | Year |
|---|---|---|---|---|
| S65B40 | 3,999 cc (244.0 cu in) | 309 kW (420 PS; 414 hp) at 8,300 rpm | 400 N⋅m (295 lb⋅ft) at 3,900 rpm | 2007 |
| S65B44 | 4,361 cc (266.1 cu in) | 331 kW (450 PS; 444 hp) at 8,300 rpm | 440 N⋅m (325 lb⋅ft) at 3,750 rpm | 2010 |
The S65B40 has a bore of 92 mm (3.6 in) and a stroke of 75.2 mm (3.0 in).
Applications:
The S65B44 is an enlarged version of the S65, due to a largerstroke of 82 mm (3.23 in).[15] It also uses a lightweight titanium exhaust.[16]
Applications:
The P65 engine is used for motor racing.
Applications:
