Metric Engine Displacement Calculator

Engine Displacement Formula:

\[ Disp_{metric} = \pi \times \left(\frac{B}{20}\right)^2 \times S \times N \]

Engine Displacement:

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1. What is Engine Displacement?

Engine displacement is the total volume of all the cylinders in an engine. It's a key measurement that indicates the engine's size and potential power output, typically measured in liters or cubic centimeters.

2. How Does the Calculator Work?

The calculator uses the engine displacement formula:

\[ Disp_{metric} = \pi \times \left(\frac{B}{20}\right)^2 \times S \times N \]

Where:

\( B \) — Bore diameter in millimeters
\( S \) — Stroke length in millimeters
\( N \) — Number of cylinders
\( \pi \) — Mathematical constant Pi (approximately 3.14159)

Explanation: The formula calculates the volume of a single cylinder (π × radius² × height) and multiplies by the number of cylinders. The division by 20 converts millimeters to centimeters for the radius calculation.

3. Importance of Engine Displacement

Details: Engine displacement is a critical factor in determining an engine's power characteristics, fuel efficiency, and emissions. Larger displacements typically produce more power but may consume more fuel.

4. Using the Calculator

Tips: Enter bore and stroke measurements in millimeters, and the number of cylinders. All values must be positive numbers. The calculator will output the total displacement in liters.

5. Frequently Asked Questions (FAQ)

Q1: Why convert millimeters to centimeters in the formula?
A: Engine displacement is traditionally measured in liters or cubic centimeters. Since 1 cm³ = 1 mL, we convert mm measurements to cm to get the result in cm³, which is then converted to liters.

Q2: What's the difference between bore and stroke?
A: Bore is the diameter of the cylinder, while stroke is the distance the piston travels within the cylinder. Together they determine the cylinder's volume.

Q3: How does displacement relate to engine power?
A: Generally, larger displacement engines can produce more power, but many other factors like compression ratio, forced induction, and engine design also significantly affect power output.

Q4: Are there different formulas for different engine types?
A: The basic formula is the same for all piston engines, but specialized engines (like rotary/Wankel engines) use different calculation methods.

Q5: Why is displacement measured in liters for automotive applications?
A: Liters provide a convenient unit for the relatively large volumes involved in engine displacement, and it's become the standard measurement unit in the automotive industry.