Engine Displacement Calculator

Calculate Engine Displacement

How to Calculate Engine Displacement

Engine displacement is a crucial measurement in automotive engineering, representing the total volume of all the engine's cylinders. It's a key factor in determining an engine's power output and efficiency.

What is the Formula?

The formula for calculating engine displacement is:

\[ \text{Displacement} = \frac{\pi}{4} \times \text{Bore}^2 \times \text{Stroke} \times \text{Number of Cylinders} \]

Where:

  • π (pi) is approximately 3.14159
  • Bore is the diameter of the cylinder
  • Stroke is the length of piston travel
  • Number of Cylinders is the total count of cylinders in the engine

What are the calculation steps?

  1. Measure the bore (cylinder diameter) and stroke length
  2. Determine the number of cylinders in the engine
  3. Apply the formula: (π / 4) × Bore² × Stroke × Number of Cylinders
  4. The result is the engine displacement in cubic units (e.g., cubic inches or cubic centimeters)

Example Calculation

Let's calculate the displacement for an engine with the following specifications:

  • Bore: 4 inches
  • Stroke: 3.5 inches
  • Number of Cylinders: 8

Step 1: Apply the formula

Displacement = (π / 4) × 4² × 3.5 × 8

Step 2: Calculate

Displacement = 0.7854 × 16 × 3.5 × 8

Displacement = 351.86 cubic inches

Step 3: Convert to other units (optional)

351.86 cubic inches = 5,766 cc = 5.77 liters

Diagram of Engine Displacement

The following diagram illustrates the key components in engine displacement calculation:

Engine Cylinder Bore (Diameter) Stroke

This diagram shows a simplified view of an engine cylinder. The bore is the diameter of the cylinder, while the stroke is the distance the piston travels within the cylinder. The engine displacement is calculated using these measurements along with the number of cylinders.