The BMW S14 four-cylinder was built in Germany from 1986 to 1991 only for the first-generation M3 (E30) coupe and convertible. There were four versions with 2.0, 2.3 and 2.5 liters: S14B20, S14B23, S14B23 Evo II and S14B25; the 2.0-liter S14B20 for tax-sensitive markets produces 192 hp.
Specifications
| Production years | 1986-1991 |
| Displacement, cc | 1990 |
| Fuel system | distributed injection |
| Power output, hp | 192 |
| Torque output, Nm | 210 |
| Cylinder block | cast iron R4 |
| Block head | aluminum 16v |
| Cylinder bore, mm | 93.4 |
| Piston stroke, mm | 72.6 |
| Compression ratio | 10.8 |
| Features | DOHC |
| Hydraulic lifters | no |
| Timing drive | chain |
| Phase regulator | no |
| Turbocharging | no |
| Recommended engine oil | 10W-40 |
| Engine oil capacity, liter | 4.5 |
| Fuel type | petrol |
| Euro standards | EURO 1 |
| Fuel consumption, L/100 km (for BMW M3 1987) — city — highway — combined |
15.7 8.6 10.8 |
| Engine lifespan, km | ~250 000 |
| Weight, kg | 188 |
The engine was installed on:
- BMW M3-Series E30 in 1986 – 1991.
Disadvantages of the BMW S14 engine
- A long-lived engine, but the cylinder head does not tolerate overheating;
- Valve clearances must be checked regularly, or the valves burn;
- Warm the engine up properly, otherwise the connecting rod bearings do not last long;
- The double-row timing chain is reliable, but its guides and tensioner are replaced often;
- The intake system with individual throttle bodies and the vacuum hoses (which last under 100,000 km and are expensive as a set) cause a lot of trouble; oil leaks, especially from the rear crankshaft seal, are also common.
Frequently asked questions about the BMW S14
How much power does the BMW S14 make?
The BMW S14 develops 192 hp and 210 Nm of torque.
How much oil does the BMW S14 take and which one?
Engine oil capacity: 4.5 liters. Recommended oil: 10W-40.
Does the BMW S14 have a timing belt or chain?
The BMW S14 uses a timing chain.
Is the BMW S14 turbocharged?
No, the BMW S14 is naturally aspirated.
Does the BMW S14 need valve clearance adjustment?
Yes, there are no hydraulic lifters, so the valve clearances have to be checked and adjusted periodically.
How long does the BMW S14 last?
The typical lifespan of the BMW S14 is ~250 000 km with proper maintenance.
What is the fuel consumption of the BMW S14?
BMW M3 1987: city 15.7, highway 8.6, combined 10.8 L/100 km.
What cars was the BMW S14 installed on?
BMW M3-Series E30 in 1986 - 1991.
What are the common problems of the BMW S14?
A long-lived engine, but the cylinder head does not tolerate overheating. Valve clearances must be checked regularly, or the valves burn. All known problems.
