Nissan varies the compression ratio between 8.0:1, a fairly low number—though typical for a turbocharged engine—and up to 14.0:1, very high for any engine, let alone one with boost.

News News by Brand Nissan News 2022 Nissan Rogue Gets Three-Cylinder, Variable-Compression Turbo Engine It promises to deliver 201 horsepower and 33 mpg combined. Peter Holderith Nov 17, 2021 10: ...

But now, Porsche has filed a patent to make a 6-stroke engine. The bottom line here is the introduction of two more strokes: Intake, compression, power, then compression, power, exhaust.

The four strokes are intake, compression, power and exhaust. A piston moves down a cylinder, sucking air (or an air-fuel mixture, in a gasoline engine) into the cylinder.

In broader terms, at 3,000 rpm, the Porsche six-stroke engine delivers 2,000 power strokes whereas a typical four-stroke will only produce 1,500 power strokes.