Home / Auto News / News article: Mazda SkyActiv-G Engines To Get 14:1 Compression Ratio - AutoGuide.com News
 |  Oct 20 2010, 11:25 AM

Mazda‘s upcoming SkyActiv-G engines will get a 14:1 compression ratio, the highest in the world for a gasoline engine, according to a report in Autoweek.

Most cars run compression ratios of 8.5:1, with high performance engines using ratios closer to 11:1. The SkyActiv-G motor takes that figure to a new level, and we’d really like to know how Mazda did it. High compression motors tend to allow for greater efficiency when it comes to making power, but too high of a compression ratio can make the engine more prone to going ka-boom.

Together with new transmissions, diesel engines, rigid chassis and weight reduction in all aspects of the car, the next-generation of Mazda’s should be pretty solid cars. Too bad they’re a few years away from hitting the market.

[Source: Autoweek]

  • Dibble1dobble

    I think they achieve the 14:1 compression ratio by pulsed exhaust phasing which has the effect of cooling the cylinder, reducing the tendency to detonation. Basically the exhaust pulse from the previous cylinder firing is used to drag the mixture from the current cylinder.

    The engine also uses direct injection with its advantage of charge cooling which also increases thermodynamic efficiency.