Bore Size Calculator

Bore Size Formula:

\[ b = 2 \times \sqrt{\frac{D}{\pi \times s \times n}} \times 1000 \]

Bore Size (b):

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1. What is Bore Size Calculation?

The bore size calculation determines the diameter of engine cylinders based on displacement, stroke length, and number of cylinders. It's a fundamental calculation in engine design and modification.

2. How Does the Calculator Work?

The calculator uses the bore size formula:

\[ b = 2 \times \sqrt{\frac{D}{\pi \times s \times n}} \times 1000 \]

Where:

\( b \) — Bore size (mm)
\( D \) — Total displacement (cc)
\( s \) — Stroke length (mm)
\( n \) — Number of cylinders
\( \pi \) — Mathematical constant pi (approximately 3.14159)

Explanation: The formula calculates the cylinder diameter required to achieve a specific displacement given the stroke length and number of cylinders.

3. Importance of Bore Size Calculation

Details: Accurate bore size calculation is crucial for engine design, performance tuning, engine rebuilding, and ensuring proper engine specifications for various applications.

4. Using the Calculator

Tips: Enter displacement in cubic centimeters (cc), stroke length in millimeters (mm), and number of cylinders. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why multiply by 1000 in the formula?
A: The multiplication by 1000 converts the result from centimeters to millimeters, as bore size is typically measured in millimeters.

Q2: What is the relationship between bore and stroke?
A: Bore and stroke dimensions determine an engine's displacement and characteristics. Different bore/stroke ratios affect engine performance, torque, and RPM capabilities.

Q3: Can this calculator be used for any engine type?
A: Yes, the formula applies to all piston engines including automotive, motorcycle, marine, and industrial engines.

Q4: How accurate is this calculation?
A: The calculation provides theoretical bore size. Actual machining may require slight adjustments based on manufacturing tolerances and specific engine requirements.

Q5: What factors affect bore size selection?
A: Cylinder wall thickness, cooling requirements, material strength, piston availability, and intended application all influence final bore size selection.