The wait for the ultimate Porsche 718 Cayman is nearly over. Next week at the LA Auto Show, Porsche is expected to reveal the new hardcore 718 Cayman GT4 RS, the fastest and lightest version of the mid-engine sports car yet.

Unfortunately for Porsche, our spies have snapped some photos of a GT4 RS performing some final testing before the big debut. This isn't the first time a pre-production model has been caught in the wild, but this one is completely undisguised, revealing the GT4 RS in all its glory for the first time.

The Porsche badge on the hood and GT4 RS logo on the wing are covered up, but the prototype is otherwise completely naked. Previous prototypes were lightly disguised with tape covering the design details, but we can now see the aggressive front splitter and the air outlets on the front fenders.

A massive swan-neck spoiler dominates the rear, generating huge amounts of downforce to keep the GT4 RS glued to the track. An additional air intake replaces the rear side quarter window. These aero upgrades enabled the GT4 RS to lap the Nurburgring in just seven minutes and 9.3 seconds, which was a massive 23.6 seconds faster than the regular 718 Cayman GT4.

The GT4 RS rides on intricately-designed center-lock wheels with a sticker covering the RS logo. The "S - RS 982" license plate could indicate this GT4 RS is a press car being put through its paces before the media gets to drive it. Another photo shows a US-spec car with ceramic brakes, confirming that the Cayman GT4 RS will be sold in the US.

Powering the GT4 RS will be the same 4.0-liter flat-six as the regular GT4 that will reportedly be uprated from 414 hp to around 450 hp, making it the most powerful 718 Cayman yet. We'll find out more details very soon. Porsche has confirmed the GT4 RS will debut this month, but a recent report suggests it will break cover on November 17 or 18 at the LA Auto Show.