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The recent dyno results for the 2.7L stroked M20 engine have shown impressive performance metrics, achieving a remarkable 230 horsepower and 200 lb-ft of torque. This significant output highlights the potential of the M20 engine when properly stroked and tuned, making it a compelling option for enthusiasts and builders alike.
Understanding the M20 Engine
The M20 engine, originally designed by BMW, is a straight-six engine that has garnered a reputation for its robust performance and tunability. With a displacement of 2.0 liters in its stock form, many enthusiasts have opted to increase its capacity through stroking, leading to substantial gains in power and torque.
Key Specifications of the M20 Engine
- Engine Type: Inline-Six
- Displacement: 2.0L (stock), 2.7L (stroked)
- Power Output: 230 hp
- Torque Output: 200 lb-ft
- Compression Ratio: Typically around 9.5:1
The Stroked M20 Build
The process of stroking the M20 engine involves increasing the crankshaft stroke, which effectively raises the engine’s displacement. For the 2.7L variant, this typically involves using a longer stroke crankshaft along with compatible pistons and rods.
Components Used in the Build
- Stroked Crankshaft: Custom or OEM options
- Pistons: High-compression forged pistons
- Connecting Rods: Upgraded rods for durability
- Cylinder Head: Ported and polished for airflow
- Camshaft: Performance camshaft for better lift and duration
Dyno Testing Process
The dyno testing process is crucial for assessing the performance of any engine build. For the 2.7L stroked M20, the testing was conducted on a chassis dynamometer to accurately measure power output at the wheels.
Steps in the Dyno Testing
- Preparation: Ensure the engine is properly tuned and all components are functioning.
- Baseline Run: Conduct an initial run to establish baseline performance.
- Load Testing: Gradually increase load to determine maximum power and torque.
- Data Collection: Record RPM, horsepower, and torque figures at various points.
- Analysis: Review data to identify areas for improvement.
Results and Analysis
The dyno results revealed that the 2.7L stroked M20 engine produced a peak power of 230 hp at approximately 6,500 RPM, with peak torque reaching 200 lb-ft at around 4,500 RPM. These figures not only demonstrate the effectiveness of the stroking process but also highlight the engine’s ability to deliver power in a usable RPM range.
Performance Characteristics
- Power Band: Strong power delivery from mid-range to high RPM
- Torque: Sufficient low-end torque for responsive acceleration
- Throttle Response: Improved throttle response due to tuning
Conclusion
The 2.7L stroked M20 engine has proven itself as a formidable option for those seeking enhanced performance from a classic BMW engine. With impressive dyno results showcasing 230 hp and 200 lb-ft of torque, it stands as a testament to the potential of proper tuning and component selection. Enthusiasts looking to maximize their M20’s performance should consider the benefits of stroking as a viable modification.