SKYACTIV-G is a family of direct injection gasoline engines. The engine compression ratio is increased to 14:1. To reduce the chance of engine knock at high compression, residual gas is reduced by using a 4-2-1 exhaust system, implementing a piston cavity, and optimizing fuel injection. In addition, combustion duration is shortened by intensifying air flow, increasing injection pressure, using multi-hole injectors, and having a piston cavity.
SKYACTIV-G 2.0[]
SKYACTIV-G 2.0 (PE-VPS) is the first engine in the SKYACTIV-G family, formerly named SKY-G.
2-liter engine displacement, 4-cylinder variant which, according to Mazda, is more fuel effective than its earlier comparable engines. By using this engine in the 2012 version of the Mazda3, they claim that with an automatic transmission, they improved fuel economy from 10.2 l/100km (23.1 miles per US gallon) to 8.4 l/100km (28.0 mpg) in town, and from 7.1 l/100km (33.1 mpg) to 5.8 l/100km (40.6 mpg) on the highway compared to the 2011 model.
SKYACTIV-G engines that do not require premium fuel, have a compression ratio of 13:1, and the resulting fuel economy and torque decreases by about 3 to 5 percent.
SKYACTIV-G 1.3[]
SKYACTIV-G 1.3 (P3-VPS) is a variant with 1,298 cc (79 cu in) engine displacement.
The engine was unveiled in 2011 Automotive Engineering Exposition.
Five Mazda engineers were awarded the 2011 Japan Society of Mechanical Engineers Medal on April 20th, 2012 specifically for the "[d]evelopment of gasoline engine (1.3L) with a super-high compression ratio and achieving fuel efficiency of 30km per liter (under Japan's 10-15 cycle)".
The engine was first used in Mazda2 13-SKYACTIV.