Calculate Bore And Stroke

Bore Calculation Formula:

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

Bore (b):

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1. What is Bore Calculation?

Bore calculation determines the diameter of engine cylinders based on displacement, stroke length, and number of cylinders. It's a fundamental parameter in engine design and analysis.

2. How Does the Calculator Work?

The calculator uses the bore calculation formula:

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

Where:

\( b \) — Bore diameter (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 bore diameter by solving the displacement equation for bore, taking into account the cylindrical volume of each cylinder.

3. Importance of Bore Calculation

Details: Accurate bore calculation is essential for engine design, performance analysis, and understanding the relationship between displacement, stroke, and cylinder dimensions in internal combustion engines.

4. Using the Calculator

Tips: Enter total 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: What is the relationship between bore and stroke?
A: Bore and stroke together determine the displacement of an engine. The bore-stroke ratio affects engine characteristics - oversquare (bore > stroke) engines typically rev higher while undersquare engines produce more torque.

Q2: Why multiply by 1000 in the formula?
A: The multiplication by 1000 converts the result from meters to millimeters, providing the bore diameter in the standard unit of measurement for engine components.

Q3: Can this formula be used for any engine type?
A: Yes, this formula applies to all piston engines including gasoline, diesel, 2-stroke, and 4-stroke engines, as long as the cylinders are circular in cross-section.

Q4: What are typical bore sizes for different engines?
A: Bore sizes vary widely: small engines (50-80mm), automotive engines (70-100mm), performance engines (90-110mm), and large diesel engines can exceed 200mm bore.

Q5: How does bore size affect engine performance?
A: Larger bore typically allows for larger valves and better breathing at high RPM, but may affect combustion chamber shape and piston speed. The optimal bore-stroke ratio depends on the intended application.