The facelifted, 991-generation 911 GT3 has appeared to spawn a test mule that is nearly identical in all areas save for its rear wing, instead employing a retractable unit found on the mainstream Carrera variants. We’ve seen this recipe before, in the form of the 911 R from before the iconic model’s facelift.

Porsche said that only 991 units of the 911 R will be made, which means that while the ingredients could turn out to be the same as that car’s, it could be called something else this time around – rumours are that the Sport Classic moniker is to be used. If the components are what the exterior suggests them to be, it will be a departure from the previous 997-generation Sport Classic in using the GT3 as a base, instead of being built around a Carrera S as before.

In contrast to the previous Sport Classic, which used a distinct ducktail spoiler, this test mule has the standard retracting item. Judging by the centre-locking wheels and overall GT3 bodywork seen here, it strongly hints at the use of a GT3 chassis, although the upcoming car could feature revised, possibly more relaxed chassis settings to distance it from the discontinued 911 R’s role of a ‘manual GT3’, now that there will be an actual manual transmission 911 GT3 due to reach markets later this year.

Given the identical, centrally-mounted exhaust outlet configuration, a similar powertrain can be expected here, namely the 4.0 litre, naturally-aspirated 4.0 litre flat-six producing 500 hp at 8,250 rpm and 460 Nm of torque at 6,000 rpm, with a rev limit increased by 200 rpm over the previous 4.0 litre engine’s (GT3 RS, 911 R) to 9,000 rpm thanks to revised internals.

In the GT3, the PDK-equipped version channels its outputs to the rear wheels via an electronically-controlled differential, while the six-speed manual employs a fully-mechanical locking unit. Chassis is identical across both two- and three-pedal GT3s, including the rear-wheel steering setup.

What also remains to be seen is the availability of the upcoming, so-called Sport Classic. The 997-generation Sport Classic was limited to 250 units and priced to match that exclusivity, and so far there has been no indication of Porsche’s approach towards this new version the 991-generation 911.

GALLERY: Porsche 991.2 911 GT3