[MSCW list] Mazda to Launch Skyactiv-X Engine with Compression Ignition in 2019

[Dave Nugent]

More good news coming out of Mazda. 

Mazda to Launch Skyactiv-X Engine with Compression Ignition in 2019

Car and Driver 8 August 2017

Mazda may be dipping into the past with its new factory effort to restore
first-generation Miatas, but the company otherwise has its sights set on the
future. Mazda announced that it is expanding its environmental initiative by
setting new efficiency, safety, and sustainability goals for the coming
decades. The most significant development is a new generation of engines,
dubbed Skyactiv-X, set to launch in 2019. Mazda claims it will be the first
commercial gasoline engine to use compression ignition technology.

Known officially as Homogeneous Charge Compression Ignition (HCCI), the
technology is something many auto manufacturers have been working on for
years. However, issues with narrow powerbands (read: unusable for normal
customers) and managing emissions have held up mass-scale implementation. An
HCCI engine pressurizes an air-and-fuel mixture until the generated heat
detonates it. It is controlled detonation, a condition to be avoided at all
costs in normal gasoline engines.

Unlike a diesel, which only always relies on compression ignition, an HCCI
engine still employs a spark plug during maximum load, or high power,
situations. Basically, Mazda will have the best of both worlds: an engine
with the cruising efficiency of a diesel without sacrificing a peppy top
end.

The company did not specify which models would get the technology, but it
did say that the Skyactiv-X engine will be supercharged to increase power
and improve response. Torque output with the new tech also is claimed to be
10 to 30 percent better than that in the current Skyactiv-G models.

The proprietary method is called Spark Controlled Compression Ignition, and
Mazda claims it improves efficiency by 20 to 30 percent from its current
Skyactiv-G engines. The efficiency and torque gains allow for "much more
latitude in the selection of gear ratios."

The HCCI news comes shortly after the company announced a partnership with
Toyota, working on EV technology. Mazda's overall goal is to cut carbon
dioxide emissions in half by 2030, from their 2010 levels. Expect more
details on Skyactiv-X later this year.