Bore Stroke Cubic Inch Calculator

Engine Displacement Formula:

\[ CI = \pi \times \left(\frac{Bore}{2}\right)^2 \times Stroke \times Cylinders \]

Engine Displacement:

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1. What is Engine Displacement?

Engine displacement refers to the total volume of all the cylinders in an engine. It's typically measured in cubic inches (CI) or liters, and represents the swept volume of all pistons moving from bottom to top dead center.

2. How Does the Calculator Work?

The calculator uses the engine displacement formula:

\[ CI = \pi \times \left(\frac{Bore}{2}\right)^2 \times Stroke \times Cylinders \]

Where:

\( Bore \) — Cylinder diameter in inches
\( Stroke \) — Piston travel distance in inches
\( Cylinders \) — Number of cylinders in the engine
\( \pi \) — Mathematical constant (approximately 3.1416)

Explanation: The formula calculates the volume of a single cylinder (πr² × stroke) and multiplies it by the number of cylinders to get total engine displacement.

3. Importance of Engine Displacement

Details: Engine displacement is a key indicator of an engine's power potential and fuel consumption. Larger displacements generally produce more power but consume more fuel. It's used for engine classification, racing categories, and performance comparisons.

4. Using the Calculator

Tips: Enter bore and stroke measurements in inches, and the number of cylinders. All values must be positive numbers. Bore and stroke measurements are typically found in engine specifications or can be physically measured.

5. Frequently Asked Questions (FAQ)

Q1: How do I convert cubic inches to liters?
A: Multiply cubic inches by 0.016387 to get liters (e.g., 350 CI × 0.016387 = 5.735 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 from top to bottom dead center.

Q3: Why is displacement important for performance?
A: Generally, larger displacement means more air/fuel mixture can be burned per cycle, resulting in more power. This is often summarized as "there's no replacement for displacement."

Q4: How does displacement affect fuel economy?
A: Larger engines typically consume more fuel as they move more air and fuel through the combustion process, though modern technology has reduced this correlation.

Q5: What are common displacement sizes for different vehicles?
A: Small cars: 1.0-2.0L (61-122 CI), midsize cars: 2.0-3.0L (122-183 CI), trucks/SUVs: 3.0-6.0L+ (183-366+ CI), performance cars: 5.0-8.0L+ (305-488+ CI).