# Engine Displacement Calculator

Calculate engine displacement from bore, stroke, and cylinder count. Get results in cc, liters, and cubic inches. Also shows bore/stroke ratio and per-cylinder volume.

## What this calculates

Engine displacement is the total volume swept by all pistons in one complete engine cycle. A Honda Civic's 2.0L engine has an 87.5mm bore, 83.1mm stroke, and 4 cylinders, giving exactly 1,998 cc. A classic Chevy 350 small block has a 4.00" bore, 3.48" stroke, and 8 cylinders for 350 cubic inches (5,733 cc).

## Inputs

- **Bore (Cylinder Diameter)** (mm) — min 10 — Diameter of each cylinder.
- **Stroke (Piston Travel)** (mm) — min 10 — Distance the piston travels from BDC to TDC.
- **Number of Cylinders** — min 1, max 16 — Total number of cylinders in the engine.

## Outputs

- **Displacement** (cc) — Total engine displacement in cubic centimeters.
- **Displacement** (L) — Total engine displacement in liters.
- **Displacement** (cu in) — Total engine displacement in cubic inches.
- **Per-Cylinder Volume** (cc) — Swept volume of a single cylinder.
- **Bore/Stroke Ratio** — Ratio > 1 = oversquare (favors RPM), < 1 = undersquare (favors torque).

## Details

The displacement formula is:

V = (pi/4) * bore2 * stroke * number of cylinders

This calculates the total swept volume, which is the volume displaced as all pistons move from bottom dead center (BDC) to top dead center (TDC).

**Bore/Stroke Ratio:**
- **Oversquare (ratio > 1):** Bore is larger than stroke. Allows larger valves and higher RPM. Common in performance engines (Ferrari, Honda VTEC).
- **Square (ratio = 1):** Bore equals stroke. Balanced characteristics.
- **Undersquare (ratio In the US, muscle car engines are traditionally measured in cubic inches (CI), while metric countries and motorcycles use cc or liters. Modern car marketing typically rounds to the nearest half-liter or whole liter (a "2.0L" might actually be 1,998 cc).

## Frequently Asked Questions

**Q: What is engine displacement?**

A: Engine displacement is the total volume swept by all pistons during one complete cycle (one up-stroke per cylinder). It is calculated from bore (cylinder diameter), stroke (piston travel distance), and the number of cylinders. A larger displacement generally means more power and torque.

**Q: What does oversquare vs undersquare mean?**

A: An oversquare engine has a bore larger than the stroke (bore/stroke ratio > 1). This allows higher RPM and larger valves for better breathing. An undersquare engine has a longer stroke, producing more torque at lower RPM. Most modern car engines are slightly oversquare.

**Q: How do I convert cubic inches to cc?**

A: Multiply cubic inches by 16.387 to get cubic centimeters (cc). For example, a 350 cubic inch engine is 350 * 16.387 = 5,735 cc, or about 5.7 liters. To go from cc to cubic inches, multiply by 0.061024.

**Q: Does more displacement always mean more power?**

A: Not necessarily. A turbocharged 2.0L engine can produce more power than a naturally aspirated 5.0L engine. Displacement determines how much air the engine can ingest per cycle, but forced induction, combustion efficiency, fuel delivery, and RPM range all affect final power output.

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Source: https://vastcalc.com/calculators/physics/engine-displacement
Category: Physics
Last updated: 2026-04-08