Automakers are experimenting extensively with 3D printing for all variety of automotive parts from simple interior trim pieces to parts as complex as brake calipers. Porsche is taking the technology a step further by experimenting with 3D-printing engine internals.
Mahle, a German parts supplier, and Trumpf, a 3D printer manufacturer, helped Porsche make 3D-printed pistons that can survive in a high-performance engine. The company 3D-printed a set of six pistons for the 911 GT2 RS with high-purity metal powder using what it calls a laser metal fusion process. Heat generated by laser beams melts the powder surface into a pre-determined shape, so this is far more advanced than your neighbor's kid's 3D printer.
Although this might sound like a PR stunt, Porsche explained 3D-printing pistons offers several significant advantages. Each piston's structure is optimized, so they weigh 10% less than comparable forged pistons, and they feature a closed, integrated cooling duct that wouldn't have been possible to add using another technique.
"Thanks to the new, lighter pistons, we can increase the engine speed, lower the temperature load on the pistons, and optimize combustion. This makes it possible to get up to 30 horsepower more from the 690-horsepower, twin-turbocharged engine [in the 911 GT2 RS] while at the same time improving efficiency," Frank Ickinger, a member of Porsche's advance drive development department, said in a statement.
There's no word yet on whether 3D-printed pistons are as durable as forged pistons. And, similarly, Porsche hasn't announced whether it plans to put them in a production car, let alone when or how much they will cost.
Porsche did say it has identified other applications for the technology. It introduced 3D-printed seat cushions in May 2020, and it offers 3D-printed versions of about 20 classic-car parts that are no longer in regular production, such as a clutch release lever that fits the 959. "This manufacturing technology is also technically and economically interesting for Porsche for special and small series as well as motorsports," the company concluded.