Engine Displacement Calculator

Enter bore, stroke and cylinders to get total displacement in cc, liters and CID — plus each cylinder's swept volume.

Engine Displacement Calculator inputs

Last updated: 2026-09-15

How the calculation works

  • Each cylinder sweeps a cylinder of bore × stroke; π/4 × d² × h gives its volume.
  • Multiply by cylinder count for total displacement; the tool converts to liters and cubic inches.

Formula

V = π/4 × bore² × stroke × cylinders
Formula variables
SymbolMeaningUnit
VSwept displacementcc
boreCylinder boremm
strokePiston strokemm

Worked example

The classic 86 × 86 mm four-cylinder: π/4 × 8.6² × 8.6 = 499.7 cc per cylinder → 1,999 cc ≈ 2.0 L, 122 CID. Bore it 0.5 mm over: 2,022 cc — the tuner's 'stroker' math in reverse.

Interpreting the result

Displacement sets the air an engine can theoretically ingest per cycle — power scales with it, airflow, and volumetric efficiency. The bore/stroke ratio shapes the character: oversquare engines rev higher (short stroke, big valves fit), undersquare make low-end torque. Oversizing bore without flow work buys compression but not power.

Assumptions

  • Cylindrical combustion space swept by the piston (chamber volume excluded — see the compression ratio calculator).
  • Nominal bore and stroke at room temperature.

Limitations

  • Wankel engines use a different volume convention (chamber × 2 typically cited).
  • Does not include gasket/deck clearance volume.

Frequently asked questions

How do I convert cc to cubic inches?

Multiply cc by 0.061 (or divide by 16.387). A 350 CID Chevy is 5,735 cc = 5.7 L; a 2.0 L engine is 122 CID.

Does displacement equal power?

No — it sets the ceiling. Volumetric efficiency, breathing, compression and RPM decide how much of that ceiling the engine reaches. A 2.0 L turbo can outperform a 3.0 L NA engine.

Related tools

Technical references