CC to HP Calculator

Estimate horsepower from engine size (cc) by engine type — and see why there's no single cc-to-HP number.

CC to HP Estimator
RESULT

There is no fixed cc-to-HP conversion — displacement is a volume, horsepower is a rate of work. But within an engine category, specific output (HP per litre) falls in predictable bands, which makes a useful planning estimate.

Quick answer: modern NA car engines make roughly 60–110 HP per litre (0.06–0.11 HP/cc); turbo engines 100–150+; sport bikes up to ~200 HP/L; small utility engines only ~30–50 HP/L.

How the Estimate Works

Estimate
HP ≈ cc × (specific output factor)
The factor is HP per cc for the engine category — set by RPM ceiling, breathing, compression and boost, not displacement alone.

Why the huge spread? Power = torque × RPM. A lawnmower engine at 3,600 RPM and a superbike at 14,000 RPM can share displacement while making 5× different power. Boost multiplies airflow again. So the honest answer to "how many HP is 2000cc" is: anywhere from ~90 HP (economy NA) to 300+ HP (high-boost turbo).

Typical HP per Litre by Engine Category

CategoryHP per litre2.0 L example
Utility (mower, generator)30–5060–100 HP
Economy car, NA55–70110–140 HP
Modern NA car70–90140–180 HP
Performance NA95–125190–250 HP
Turbocharged street110–150220–300 HP
Sport motorcycle150–200300–400 HP-equivalent

To compute displacement itself from bore and stroke, use the engine displacement calculator; to convert between cc, litres and cubic inches, use the engine size converter.

Worked Example

Worked Example
1. A 1,998 cc modern NA engine
2. Factor ≈ 0.08 HP/cc
3. HP ≈ 1998 × 0.08 ≈ 160 HP (typical range 140–180)
How this calculator is checked

Specific-output bands are compiled from published manufacturer specs across each engine category. This is a planning estimate — actual output depends on tune, breathing and boost, not displacement alone.

Frequently Asked Questions

For small utility engines, the old rule of thumb is 1 HP per ~30–35 cc. Car engines are far more powerful per cc — closer to 1 HP per 12–15 cc.

Typically 90–130 HP naturally aspirated, or 130–180+ HP turbocharged. Motorcycle 1500s and utility 1500s fall well outside that band in opposite directions.

Displacement is how much air the engine can swallow per revolution; power also depends on how fast it revs and how densely the air is packed (boost). Same cc, very different HP.