BMW S65 Engine (S65B40)
|Also called||BMW S65|
|Cylinder block alloy||Aluminum|
4 valves per cylinder
|Piston stroke, mm (inch)||75.2 (2.96)
|Cylinder bore, mm (inch)||92 (3.62)
|Displacement||3999 cc (244 cu in)
|Power output||309 kW (420 HP) at 8,300 rpm
|Torque output||400 Nm (295 lb·ft) at 3,900 rpm
|HP per liter||105
|Weight, kg (lbs)||202 (445)|
|Fuel consumption, L/100 km (mpg)
|for E90 M3
|Oil consumption, L/1000 km
(qt. per miles)
|up to 1.0
(1 qt. per 750 miles)
|Recommended engine oil||10W-60
|Engine oil capacity, L (qt.)||8.8 (9.3)|
|Oil change interval, km (miles)||5,000-10,000
|Normal engine operating temperature, °C (F)||–|
|Engine lifespan, km (miles)
-No life span loss
|The engine is installed in||BMW M3 E90/E92|
In comparison with E46 M3, BMW M3 E90/E92 gained about 200 kg, and it means that S54 is not enough for a dynamic driving. That is why in the next generation of M3 used V8 – S65B40.
This motor based on S85B50 by removing two cylinders and turn it into a V8 with 4 liter capacity. The cylinder block is the same as on S85, cylinder spacing – 98 mm, rod length is 140.7 mm and pistons are the same as on M5-engine.
The cylinder head design is similar, but variable valve timing system Double-VANOS was redesigned and absent high pressure oil pump. Timing range of camshafts: intake 58 °, exhaust 48 °. Specs of M3 E92 camshafts: duration 256/256 deg, lift 11.35/11.35 mm. Valves and springs are similar as on S85. On intake used individual throttle bodies (two rows of 4), with optimized the intake manifold. Capacity standard of fuel injectors – 192 cc/min. On an exhaust installed headers 4-1. BMW S65 firing order: 1-5-4-8-7-2-6-3.
The engine control unit is Siemens MS S60. Thanks to all this, the S65B40 develops 420 horsepower at 8,300 rpm, and redline installed on 8,400 rpm. This engine intended only for BMW M3 E90/E92/E93. BMW S65 produced until 2013, after which it replaced by turbocharged S55.
BMW S65B40 engine problems and malfunctions
The design and problems are the same as in V10 S85. Learn about them more in details HERE.
S65 performance upgrades
The most popular way to increase the power of BMW E92 M3 is buying the performance exhaust system (like Supersprint), replacing filters and a new ECU software.
It give up to 450 horsepower and more aggressive sound that will enhance the sensations. If you want 480 horsepower, then buy camshafts 286/286 deg, lift 12/12 mm. You can increase displacement to 4.6 liter if buy S65 stroker kit. Such sets include the crankshaft with a piston stroke of 82.7 mm, with pistons of 94 mm and with the corresponding rods. If you keep on stock pistons, then you get 4.4 liter capacity. With such stroker kit and cams, your naturally aspirated S65 will show more than 500 horsepower.
But it is much more favorable to buy ESS supercharger kit. They can be installed on stock internals and without problems pass many thousands of km. For stock engine VT2-625 will be a reasonable limit. The maximum boost – 6.5 psi (0.45 bar), it allows to get 625 horsepower. Don’t forget to buy ESS connecting rod bearings, it will increase reliability. If you want 700+ horsepower, then you should decreased compression ratio and spend much more money.