2.0-L DOHC Turbo engine

A newly developed DOHC cylinder head is used in this engine. The intake port and the combustion chamber have been redesigned to reduce residual gasses, thus raising combustion efficiency.

By using a resin-based intake manifold, the inner walls of the manifold are smooth and less resistant to the intake flow. The weight is also reduced by 30% compared to the earlier manifold.

A design change in the cooling water channel around the spark plug further prevents engine knocking and also helps improve low-end and mid-range torque output.

The injector nozzle has been redesigned to atomize fuel and finely disperse it into the combustion chamber for improved combustion. This also helps reduce harmful substances in emissions.

Also adopted is a secondary air system that forces air into the exhaust port to burn out any gasoline remaining in it. The system helps eliminate harmful substances when the powertrain is still cool, and it promotes early activation of catalytic converters.

The twin mufflers expand the muffler capacity, bringing noise levels down even lower and reducing exhaust back pressure.

Powered by regular gasoline, the 2.0-L naturally aspirated Boxer engine features better combustion efficiency, as well as eco-friendly performance and fuel economy, thanks to a newly designed DOHC cylinder head and the use of the active valve control system (AVCS).

    See also:

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