Overview of the S38 Engine
The S38 engine is a legendary piece of engineering that has carved its niche in the annals of automotive history. Introduced in the mid-1980s, this high-performance inline-six engine was designed by BMW to power some of its most iconic models, particularly the M5 series. The S38 is a naturally aspirated engine that showcases BMW’s commitment to performance and precision engineering. With its robust design and impressive output, the S38 quickly garnered a reputation for delivering exhilarating driving experiences.
The S38 engine is characterized by its DOHC (dual overhead camshaft) configuration, which enhances airflow and overall efficiency. This design choice allows for higher RPMs and improved throttle response, making it a favorite among enthusiasts and racers alike. The engine was built with a focus on performance, featuring a forged steel crankshaft, lightweight aluminum block, and a sophisticated fuel injection system that optimizes power delivery.
One of the standout features of the S38 is its ability to produce a substantial amount of horsepower while maintaining a smooth and responsive driving feel. The engine’s engineering is complemented by BMW’s meticulous attention to detail, resulting in a powerplant that not only performs well but also stands the test of time.
Applications of the S38 Engine
The S38 engine found its home in several notable BMW models, primarily the M5 variants. Here are the key models that utilized the S38:
– BMW E28 M5 (1982-1988): The first generation of the M5, the E28, was equipped with the S38B35 variant of the engine, producing around 256 hp. It set the standard for performance sedans and is often credited with establishing the M5’s reputation as the “original super sedan.”
– BMW E34 M5 (1988-1995): The second generation, E34 M5, took the S38 to new heights with the S38B38 version, which produced around 340 hp. This model introduced more advanced technology and comfort features while retaining the raw performance that enthusiasts craved.
– BMW M6 (E24, 1983-1989): The S38 engine was also used in the M6, which shared many components with the M5. The M6 offered a more luxurious experience while still delivering the thrilling performance that the S38 was known for.
– BMW M635CSi (E24, 1982-1989): This model showcased the S38 engine’s capabilities in a sportier coupe format, combining performance with elegance.
In essence, the S38 engine represents a significant chapter in BMW’s performance lineage, symbolizing the brand’s dedication to engineering excellence and driving pleasure. Its applications in the M5 and other models solidified its status as a cornerstone of BMW’s performance heritage.
Specifications of the S38 Engine
The S38 engine is a remarkable piece of machinery that combines advanced engineering with high-performance capabilities. Below, we delve into the detailed specifications of the S38 engine as used in the E28 and E34 M5 models, providing insights into its design and performance metrics.
BMW S38 (E28 M5)
The E28 M5, introduced in 1982, was the first of its kind and set the benchmark for future performance sedans. The S38B35 engine variant powered this model, showcasing a blend of power and refinement.
| Specification | Details |
|---|---|
| Engine Type | Inline-6, DOHC |
| Displacement | 3.5 liters (3453 cc) |
| Power Output | 256 hp (190 kW) at 6,500 RPM |
| Torque | 243 lb-ft (330 Nm) at 4,750 RPM |
| Compression Ratio | 10.0:1 |
| Fuel System | Motronic fuel injection |
| Ignition System | Electronic ignition |
| Maximum RPM | 7,000 RPM |
| Oil Capacity | 6.5 quarts (6.2 liters) |
| Oil Recommendation | SAE 15W-40 or 10W-40 |
BMW S38 (E34 M5)
The E34 M5, launched in 1988, refined the performance sedan concept further. The S38B38 engine variant introduced in this model brought enhancements in power and efficiency.
| Specification | Details |
|---|---|
| Engine Type | Inline-6, DOHC |
| Displacement | 3.8 liters (3795 cc) |
| Power Output | 340 hp (250 kW) at 6,750 RPM |
| Torque | 369 lb-ft (500 Nm) at 4,750 RPM |
| Compression Ratio | 10.0:1 |
| Fuel System | Motronic fuel injection |
| Ignition System | Electronic ignition |
| Maximum RPM | 7,200 RPM |
| Oil Capacity | 7.5 quarts (7.1 liters) |
| Oil Recommendation | SAE 15W-50 or 10W-40 |
The specifications of the S38 engine reflect its engineering prowess and the commitment to performance that BMW is known for. Each variant of the S38 engine is tailored to deliver a unique driving experience, making the E28 and E34 M5 models true icons in the world of performance cars.
Common Problems and Reliability of the S38 Engine
The S38 engine, while celebrated for its performance and engineering, is not without its issues. Owners and enthusiasts have reported several common problems that can affect the engine’s reliability over time. Understanding these issues is crucial for anyone considering a vehicle equipped with the S38, whether it’s an E28 or E34 M5.
Common Problems
While the S38 engine has a reputation for durability, it can encounter specific problems, especially as it ages. Here are some of the most frequently reported issues:
– Head Gasket Failure:
– One of the most critical issues is head gasket failure, often caused by overheating or age. This can lead to coolant leaks and engine overheating, which can cause severe damage if not addressed promptly.
– Oil Leaks:
– Oil leaks are common, particularly from the valve cover and oil pan. Over time, gaskets can wear out and lead to noticeable leaks, which can affect engine performance and longevity.
– Timing Chain Tensioner Issues:
– The timing chain tensioner can wear out, leading to a rattling noise at startup. If not replaced, this can result in timing chain failure, which can cause catastrophic engine damage.
– Fuel Injector Problems:
– Fuel injectors may become clogged or fail, leading to rough idling, poor fuel economy, and loss of power. Regular maintenance is essential to prevent this issue.
– Cooling System Failures:
– The cooling system components, such as the radiator and water pump, can fail, leading to overheating. Regular checks and maintenance of the cooling system are crucial to prevent overheating.
Reliability Factors
The reliability of the S38 engine largely depends on maintenance and care. Here are some factors that can influence its longevity:
– Regular Maintenance:
– Adhering to a strict maintenance schedule is vital. Regular oil changes, coolant flushes, and inspections can prevent many common problems.
– Quality of Parts:
– Using OEM or high-quality aftermarket parts can significantly impact the engine’s reliability. Cheap replacements can lead to further issues down the line.
– Driving Habits:
– How the vehicle is driven plays a crucial role in its longevity. Aggressive driving can put extra stress on the engine, leading to premature wear.
– Previous Ownership:
– The history of the vehicle is essential. A well-maintained S38 engine from a responsible owner is likely to be more reliable than one that has been neglected.
In summary, while the S38 engine is a robust and capable powerplant, it is essential for owners to be aware of its potential issues and take proactive measures to ensure its reliability. Regular maintenance and attention to common problems can help keep the S38 running smoothly for years to come.