New special-edition to be revealed in Goodwood with GT3 power

A development vehicle believed to be the new Porsche 911 Speedster has been spotted during hot-weather testing in Southern Europe.

Spotted in convoy with several Porsche GT models including the 911 GT3 and GT3 RS, the prototype wears a similar body and wheel/tyre package to the hardtop GT variants, though with the absence of a fixed rear wing and, obviously, the retractable fabric roof.

Power is said to come from the same 4.0-litre flat six that features in the GT3, meaning an output of 373kW is very likely. We'd argue both manual and dual-clutch PDK transmissions will be offered, too.

Further details are hard to come by, but it's believed the new 911 Speedster will be revealed at the 2018 Goodwood Festival of Speed, which commences on July 12.

Expect a very limited production run as well, to preserve exclusivity. Just 356 of the previous 911 Speedster, a nod to the name of Porsche's iconic 356 Speedster.

Stay tuned to CarAdvice for all the latest updates in the lead-up to the Goodwood event, and head to the gallery for more images.