1. What is the Wallace Racing CI Formula?

The Wallace Racing CI (Cubic Inch) formula calculates engine displacement based on bore diameter, stroke length, and number of cylinders. It's a standard method used in automotive engineering to determine engine size and performance potential.

2. How Does the Calculator Work?

The calculator uses the Wallace Racing CI formula:

Where:

• \( B \) — Bore diameter (inches)
• \( S \) — Stroke length (inches)
• \( Cyl \) — Number of cylinders
• 0.7854 — Constant (π/4)

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

3. Importance of Engine Displacement Calculation

Details: Engine displacement is a key factor in determining engine power, torque, and efficiency. It's essential for engine building, performance tuning, and classification in racing categories.

4. Using the Calculator

Tips: Enter bore and stroke measurements in inches, and the number of cylinders. All values must be valid positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why is 0.7854 used in the formula?
A: 0.7854 is π/4, which is used to calculate the area of a cylinder bore (πr²) where r = B/2, so π(B/2)² = πB²/4 = 0.7854B².

Q2: How accurate is this calculation?
A: The formula provides theoretical displacement. Actual displacement may vary slightly due to manufacturing tolerances and combustion chamber design.

Q3: Can I use metric measurements?
A: This calculator uses inches. For metric measurements (mm), convert to inches first (1 inch = 25.4 mm) or use a metric-specific formula.

Q4: Does this account for engine compression ratio?
A: No, this calculates total displacement only. Compression ratio is a separate calculation based on combustion chamber volume.

Q5: What's the relationship between displacement and power?
A: Generally, larger displacement engines can produce more power, but efficiency, design, and forced induction also significantly affect power output.