Porsche’s six-stroke engine
Who loves a good internal combustion engine (ICE)? Confession time would have me say that I still love the special characteristics of an ICE and the awesome soundtracks that they can make – none being more special than a sonorous and legendary V8 or even a fully vocal high-pitched straight six.
Now there is news in the hood that Porsche has patented some new technology whereby the introduction of a six-stroke cycle for an ICE of theirs will be made. The common four-stroke cycle that is already used by almost every auto manufacturer, including Porsche, has four strokes: intake, compression, ignition, and exhaust. Porsche states that the six-stroke cycle will make considerable gains in power output while also lowering its levels of emissions. This is great news for ICE fans.
How does it work and what’s the difference? As the numbers suggest, the conventional four-stroke cycle makes a power stroke one in every four times that the piston moves on its vertical axis. Thus, in a conventional four-stroke engine, each piston helps to drive the car about 25% of the time. Porsche’s new six-stroke engine will provide a power stroke twice in its six-stroke cycle – that’s two power strokes out of every six that the piston moves on its vertical axis (or one in three). This means that each piston is helping to power/drive the vehicle about 33% of the time it’s moving. The six-stroke cycle works as follows: intake fuel and air, compress the fuel and air mix, ignition (power), intake more fuel and air, ignition (power), and exhaust.
By allowing the piston to have a variation in its travel length inside its chamber via clever internal gearing and a special vent design, the six-stroke engine can produce more power strokes within its cycle. For the first three strokes, the piston works like a normal four-stroke. Then, on the fourth stroke, the special gearing allows the piston to drop lower in its chamber, presenting some more scavenging ports that allow more fuel and fresh air to enter the cylinder while the exhaust gases escape out the exhaust ports. The fifth stroke ignites the fresh fuel mix, and then the sixth cycle gets rid of all burnt/spent gases.
Who wouldn’t want a great sounding faster and more efficient new Porsche sports car? However, this is not all that the clever team at Porsche have been up to. Porsche has already worked towards creating a fuel that is considered to be a carbon-neutral synthetic fuel made from carbon dioxide (CO2) that has been captured from the atmosphere. That’s right, it is essentially using or recycling atmospheric carbon as fuel for their ICE vehicle.
While still leading the charge for ICE fans, Porsche has not abandoned EVs. It is also worth noting that Porsche is also going in all guns blazing with EV technology as well. Most new models of Porsche have an EV in their line-up already, and the Taycan is a pure EV.
All the same, I’m fascinated by this new six-stroke technology and am looking forward to seeing it in whatever new offerings Porsche decides to serve up.