Porsche appears set to roll out with an updated version of its 911 RSR, which is believed to center around a switch to a turbocharged powerplant, in time for the 2019-20 FIA World Endurance Championship season.

Leading German motorsports publication Auto Motor und Sport has revealed a series of spy photos of the new generation GTE contender, which was caught testing in a pre-production phase in Weissach.

While featuring visible changes to the side cooling vents, the photos also show external exhaust tubes, indicating early experimentation of a potentially new exhaust layout.

According to those that have heard it in person, including the photographer, the car sounds like a “vacuum cleaner” and not like the current high-pitched scream of its 24 Hours of Le Mans GTE-Pro class-winning 911 RSR.

The German manufacturer has yet to acknowledge or confirm existence of the car, although Head of Motorsport Dr. Frank-Steffen Walliser has previously hinted of another new project in the works for 2019.

Porsche has already announced plans for new GT3 and GT4-spec machinery that will be rolled out next year, with a GT2-spec car, based on the 911 GT2 RS, also likely at some stage.

It’s understood the new-gen GTE car could be revealed at Porsche’s Rennsport Reunion at WeatherTech Raceway Laguna Seca later this month.

Whether it would be considered an all-new car or rather an Evo kit, however, remains unclear, although an engine change would likely require a new homologation.

Should the switch be made, it would result in an all-turbo GTE field by 2020, once Corvette’s new mid-engined C8.R debuts.

Under current rules, new cars would only be able to debut at the start of the new GTE regulations cycle, which is slated to begin with the 2019-20 WEC season-opener at Silverstone in September.

IMSA will adopt the next three-year cycle beginning with the 2020 Rolex 24 at Daytona.