The smallest Honda car engine is a 658 cc inline-three designed for Honda’s kei cars.
This engine sits within Japan’s kei-car class, which caps displacement at 660 cc, shaping Honda’s ultra-compact city-motoring strategy.
Defining the smallest engine in Honda's lineup
In practical terms, Honda’s smallest road-going engines are in the 0.66-liter, three-cylinder family that powers kei cars. The best-known example is the S660, a lightweight kei roadster launched in 2015 with a 658 cc engine. Across the kei lineup, most models use engines in the 658–660 cc range, optimized for efficiency, compact packaging, and reliability rather than high performance. These powerplants are engineered to maximize interior space while complying with strict kei-car regulations in Japan and other markets that offer ultra-compact options.
Notable examples
Below are representative examples of Honda's smallest-displacement engines and the models that use them.
The S660: 658 cc inline-three powerplant
The S660 is Honda's modern kei roadster, introduced in 2015, powered by a compact 658 cc three-cylinder engine designed to deliver nimble performance in a tiny package.
Kei-family cars: N-Box, N-One, N-WGN
These popular kei cars use around 660 cc-class three-cylinder powerplants. They illustrate how Honda packs efficiency, space, and affordability into ultra-compact footprints.
Commercial kei models: Acty and related vans
Honda's kei commercial line, including the Acty, uses similar displacement engines to maximize payload while meeting kei regulations.
Across these lines, the 658–660 cc range represents Honda's smallest engines in production for road cars in recent years, reflecting regulation-driven design rather than a broader push into ultra-small variants.
Historical context and future direction
Honda has long pursued efficient powertrains for city cars, balancing compact displacement with modern technology. In kei cars, engineers have used both naturally aspirated and turbocharged variants to achieve acceptable performance within the class limits. In recent years, some models have explored additional efficiency gains through hybridization and advanced transmission options to meet tightening emissions targets without sacrificing practicality.
Summary
In short, Honda's smallest car engine is a 658 cc inline-three, typical of the kei-class powertrains that define the brand’s tiniest lineup. These engines reflect Honda’s focus on ultra-compact, efficient city motoring—designed to maximize interior space and fuel economy within strict regulatory limits.