Since 1992, the basic 3-liter M3 sedan, coupe, and convertible sports engine has been manufactured for the European market (S50B30 EU). This 300 horsepower engine was fitted to a limited edition M3 GTR E36 coupe in 1994. A year later, a 295 horsepower version with 324 Nm of torque was added to the M3 GT E36 racing model. This power unit was also upgraded in 1995 for the Australian racing version of the M3-R E36 coupe by BMW Motorsport and Schnitzer Motorsport GmbH.
Specifications
| Manufacturer | Munich Plant |
| Also called | S50 |
| Production years | 1992-1995 |
| Cylinder block alloy | cast iron |
| Fuel system | injector |
| Configuration | inline |
| Number of cylinders | 6 |
| Valves per cylinder | 4 |
| Piston stroke, mm | 85.8 |
| Cylinder bore, mm | 86 |
| Compression ratio | 10.8 (EU) 10.5 (US) |
| Displacement, cc | 2990 |
| Power output, hp | 243 /6000 rpm 286 /7000 rpm 295 /7100 rpm |
| Torque output, Nm / rpm | 305 /4250 rpm 320 /3600 rpm 323 /3900 rpm |
| Max engine speed, rpm | 7280 (EU) 6500 (US) |
| Fuel type | petrol |
| Euro standards | Euro 1 |
| Weight, kg | 151 (EU) 135 (US) |
| Fuel consumption, L/100 km — city — highway — combined |
11.8 8.4 9.1 |
| Oil consumption, gr/1000 km | up to 1000 |
| Recommended engine oil | 5W-30 / 5W-40 / 5W-50 / 10W-40 / 15W-40 |
| Engine oil capacity, liter | 7.0 |
| Normal engine operating temperature, °C | ~90 |
| Engine lifespan, km | ~400 000 |
| Transmission — 5MT — 5AT |
ZF Type C ZF 5HP18 |
| Gear ratios, 5MT | 1 — 4.20 / 2 — 2.49 / 3 — 1.66 / 4 — 1.24 / 5 — 1.00 |
| Gear ratios, 5AT | 1 — 3.67 / 2 — 2.00 / 3 — 1.41 / 4 — 1.00 / 5 — 0.74 |
| Final drive ratio — 5MT — 5AT — 5MT (M3 GT, M3 CSL LTW) |
3.15 3.23 3.23 |
Disadvantages of the S50B30 engine
Increased oil consumption, overheating, leaks, floating speed, issues with the Vanos system, and intake air leaks are typical S50B30 engine malfunctions.
Overheating of the motor is a common occurrence. You should examine the cooling system’s operation, including the radiator, thermostat, and pump, if you see any issues. Broken radiator caps and air obstructions in the system can result in overheating.
A malfunctioning idle valve is frequently the cause of unstable turnovers. The valve is cleaned and then operates again. If the issue continues, you should check the temperature sensor, lambda probe, and throttle position sensor. Sometimes cleaning the throttle valve is sufficient.
Examine the spark plugs, injectors, and ignition coils if the engine triples. When the Vanos system malfunctions, the engine starts to rumble, power drops, and speed becomes erratic. You must purchase a Vanos repair kit in this case.
High oil consumption—up to 1 liter per 1000 kilometers—is a characteristic of motors with high wear. Consumption is essentially unchanged even after a significant engine overhaul. It is essential to verify that the sump and valve cover gaskets are leak-free and to rule out leaks using an oil dipstick. Examine the expansion tank’s integrity as it may be the source of the antifreeze leak. Temperature sensors, camshafts, and crankshafts can all cause issues.
The age of the power units is the primary cause of the failure of dependable S50B30 engines.