difference between horsepower and CC | small engine

Explanation of the relationship between CC and horsepower

In the most crucial part of our article, BISON will discuss with you in depth the difference between cc and hp. The relationship between cc and hp is complex and challenging to explain because it depends on many factors. Cc and hp are not the same, but there is a general relationship between the two.

Nature of the measurement

• Cubic centimeters: The ‘cubic capacity’ measured in cc refers to the overall volume of the engine – all cylinders included. This volume can also be thought of as the engine’s size or displacement. It indicates the engine’s capacity to hold a mixture of air and fuel for combustion.
• Horsepower: HP is the unit of power measurement (measured in kilowatts) and is usually calculated as peak power. It measures the rate at which an engine can perform work, specifically 550 foot-pounds of work per second. This essentially reflects the engine’s ability to convert fuel into usable mechanical energy.

Analogies for better understanding

At BISON, we have an interesting analogy that can help you better understand the concepts of cc and hp：

Think of cc as the size of a glass – how much liquid (mixture of air and fuel) the glass has the potential to hold.

Think of hp as the amount of juice in the glass. The juice represents the actual power or useful energy derived from the liquid.

A larger jar (higher cc) has the potential to hold more liquid (fuel and air mixture). However, the actual amount of juice (hp) you get depends on how efficiently you fill the glass and the liquid quality.

Correlation, but modern technological advancements

Although cc and hp measure different things, they are related:

Generally, a higher cc usually means the engine has the potential to produce more hp because it can burn more fuel each cycle. However, this relationship is not always direct or linear. The design and efficiency of the engine play significant roles.

Today’s engineering advancements allow for the development of engines with lower displacement (low cc) but high horsepower. For instance, a large engine (high cc) might not yield high horsepower if it is not designed efficiently. Conversely, a smaller engine (low cc) can produce high horsepower with modern engineering and technology, which is highly efficient and environmentally friendly.

For example：

1. Different CCs and different hpoutputs:
   Imagine two machines with different cc’s:
   Machine A: 210 cc engine
   Machine B: 389 cc engine
   Machine B, with a larger displacement, generally has the potential to produce more horsepower when measuring the amount of juice in a glass (available power). However, if Machine A (BISON BS168F) is more technologically advanced in design and efficiency, it may produce comparable or even more horsepower than Machine B.

2. Same displacement, different hp:
   Consider two engines with the same displacement:
   Engine X: 420 cc, producing 13 hp
   Engine Y: 420 cc, producing 15 hp
   For example, turbocharged engines can compress more air into the cylinders, allowing for more fuel to be burned and, thus, increasing horsepower without increasing the engine’s size. Engine Y (BISON BS190F) uses advanced technologies to extract more power from the same volume.

Understanding the nuanced interplay between cc and hp helps in assessing an engine’s performance. While the cc gives an idea of the potential capacity, the hp measures the actual power output and efficiency. Modern technological advances allow lower displacement engines to produce more power, emphasizing the importance of a comprehensive approach to engine design and evaluation.