What's the difference between BHP, HP and PS? - Mike's Mechanics

Introduction

Understanding engine power figures can be confusing due to the variety of units used, including horsepower (HP), brake horsepower (BHP), and PS (Pferdestärke). This tutorial aims to clarify the differences between these units, helping you make sense of car performance metrics.

Step 1: Understanding Horsepower

• Definition: Horsepower is a unit of measurement that quantifies the power of an engine.
• Standard Measurement: One horsepower is equivalent to approximately 746 watts.
• Usage: Commonly used in the United States to describe engine power.

Step 2: Exploring Brake Horsepower

• Definition: Brake horsepower measures the engine's output before losses from the drive train (like gear and friction).
• Key Point: BHP is typically higher than HP as it does not account for the power lost through the vehicle's transmission.
• Application: Used mainly in the UK and Europe for performance assessment.

Step 3: Understanding PS (Pferdestärke)

• Definition: PS stands for Pferdestärke, which translates to “horsepower” in German. It is slightly different from the traditional horsepower.
• Conversion: 1 PS is approximately equal to 0.986 HP or 0.986 BHP, making it a bit less than the standard HP.
• Usage: Commonly used in Europe, especially in the automotive industry, to describe engine power in cars.

Step 4: Comparing the Units

• Quick Reference:
  • 1 BHP ≈ 1.014 HP
  • 1 PS ≈ 0.986 HP
• Understanding Differences:
  • HP is used primarily in the US.
  • BHP is often preferred when determining engine performance in a controlled environment.
  • PS is prevalent in European markets.

Step 5: Practical Implications

• Selecting the Right Unit: Depending on your location or the car market you are dealing with, the preferred unit may vary.
• Interpreting Performance Figures: Always consider the unit being used when comparing engines and their performance metrics.

Conclusion

In summary, horsepower, brake horsepower, and PS are essential units for measuring engine power, each with its own context and application. Understanding these differences allows for better comparisons and evaluations of vehicle performance. As you delve deeper into automotive topics, be aware of these units to enhance your knowledge and discussions about car engines. If you have any specific questions or topics you'd like to explore further, feel free to reach out!