Engine Horsepower Calculator - calculatorsee.com


Engine Horsepower Calculator

Calculate engine cubic inch displacement (CID), cubic centimeters (cc), liters, and potential naturally aspirated horsepower from cylinder bore and stroke.

Calculator Inputs

in
Cylinder diameter (e.g. 4.00" for Chevy 350).
in
Crankshaft stroke (e.g. 3.48").
Cylinder count.
RPM
Peak RPM.

Calculated Results

Engine Displacement
350 CID (5.73 Liters / 5,733 cc)
Naturally Aspirated Horsepower 365 HP (Street Performance)
Bore / Stroke Ratio 1.15 (Over-square / Rev-happy)
Piston Speed at 5,800 RPM 3,364 ft/min
Values calculate live as you adjust inputs.

About Engine Horsepower Calculator

Computes total internal combustion engine swept displacement from cylinder bore diameter, stroke length, and cylinder count.

What is Engine Horsepower Calculator?

Computes total internal combustion engine swept displacement from cylinder bore diameter, stroke length, and cylinder count.

How to Use This Calculator

  1. Enter bore and stroke in inches.
  2. Select number of cylinders.
  3. Review displacement in CID, cc, and liters.

The Mathematical Formula & Variables

Displacement (CID) = 0.7854 * Bore^2 * Stroke * Cylinders; Liters = CID * 0.016387

Step-by-Step Worked Example

Scenario: Small Block V8 with 4.00" bore and 3.48" stroke.

  1. Single cylinder volume = 3.14159 * 2^2 * 3.48 = 43.73 cu in.
  2. 8 cylinders = 43.73 * 8 = 349.85 cu in (classic 350 CID).
  3. In liters: 350 * 0.016387 = 5.73 Liters.

Result: 350 CID (5.73L V8)

Frequently Asked Questions

What does over-square mean in engine design?

An over-square (short-stroke) engine has a bore diameter larger than its stroke, allowing higher RPM operation with reduced piston speeds.