SKYACTIV-G (Gasoline Engine) —A Technical Explanation by one of Mazda's Engineers—

Increasing the compression ratio greatly improves thermal efficiency. However, in a gasoline engine, it also increases the likelihood of premature ignition (knocking) because the extra pressure causes the fuel to get too hot, so it starts to combust too early. Mazda's SKYACTIV-G solves this problem by adopting a new 4-2-1 exhaust manifold and enhanced gasoline injection technology. The result is the world's highest compression ratio of 14.0:1 and 15% more torque at low- to mid-engine speeds compared to the current engine.

Category:

Autos & Vehicles

Tags:

• mazda
• skyactiv
• technology
• gasoline
• petrol
• engine
• direct
• injection

[somerandomaussie]

so this is mazdas fancy name for direct injection? been out for awhile now :/

[egoldberg85]

Nope. Supposed to be okay with 87 octane. 

[markaruski]

I'm interested in this car very much -- only one thing holding me back: concerns over Direct Injection 'gunking' / intake valve deposit build up. What have Mazda's engineers done to address Direct Injection durability w/ respect to this issue (which Audi / VW have had problems with, since there is no 'wash' of fuel detergent over the intake valves)?

[sangolt88]

Maybe we can see this engine in Mazda 6 soon? Lets say a direct injection 1.6l 140 HP?

[killamajiger]

Does it require premium fuel to achieve the higher compression ratios?