What is bhp?

Brake Horsepower (bhp)

Brake horsepower (bhp) is a measure of an engine's power output, specifically the power available at the engine's flywheel after accounting for losses due to internal friction. This means it represents the power that can be used to perform work, such as turning the wheels of a vehicle or powering machinery.

Here's a breakdown of key aspects:

• Definition: BHP quantifies the power produced by an engine before the power is lost to components like the gearbox, alternator, and other auxiliary systems. It differs from indicated horsepower (ihp), which is the theoretical power developed in the cylinders without accounting for friction.

• Measurement: BHP is typically measured using a dynamometer (dyno). The engine is connected to the dyno, which applies a load. The dyno then measures the torque and rotational speed (RPM) of the engine. From these measurements, the BHP is calculated using the following formula:

  BHP = (Torque (lb-ft) x RPM) / 5252

• Significance: BHP is a crucial metric for evaluating an engine's performance. It provides a standardized way to compare the power output of different engines, irrespective of the vehicle or application they are used in. Higher BHP generally indicates a more powerful engine, capable of delivering greater acceleration and top speed (depending on other factors like gearing and aerodynamics).

• Factors Affecting BHP: Several factors can affect an engine's BHP, including:

  • Engine size and design
  • Compression ratio
  • Fuel type and delivery system
  • Intake and exhaust systems
  • Engine tuning and calibration

• Relationship to other Power Units: BHP is related to other power units, such as horsepower (hp) and kilowatt (kW). Although often used interchangeably, BHP specifically refers to the power output at the flywheel, whereas hp can sometimes refer to power measured at the wheels (wheel horsepower, whp). Kilowatts are the metric unit of power, with 1 hp being approximately equal to 0.746 kW.

Here are some key subjects as links:

• Engine's Power Output
• Dynamometer
• Torque
• RPM
• Kilowatt