In case that giant wing didn’t tip you off, this is a prototype Porsche 718 Cayman GT4 RS.

    When it debuts, likely sometime this year, it’ll become the ultimate Cayman.

    It’s likely to pack a more powerful version of the GT4’s 4.0-litre naturally-aspirated flat six, which makes 309kW of power and 420Nm of torque.

    Overseas reports suggest a power output of between 335kW and 372kW. That would have it tailgating the Porsche 911 GT3 RS uncomfortably closely.

    The GT3 RS variant of the previous 991 generation 911 produced 383kW of power and 470Nm of torque from its 4.0-litre flat six.

    We don’t yet know the outputs of the upcoming 992 GT3 RS, which has been spied testing and is expected to debut this year.

    The Cayman GT4 RS being tested has little camouflage but for some on the front bumper, the front fenders, and the rear-quarter windows.

    The camouflage on the front fenders may be concealing more aggressive front fenders with vents atop them.

    That swan-neck rear spoiler mimics the one fitted to the 911 GT3 prototypes spied recently, and the centre lock wheels are similar to those fitted to the previous GT3 RS Weissach.

    Although previous speculation suggested the swan-neck spoiler was purely for development, Porsche has since confirmed a very similar unit will feature on the 911 GT3, making it a likely addition to the Cayman GT4.

    Other changes from the GT4 include different exhaust outlets, NACA ducts in the bonnet and a deeper front splitter.

    MORE: Porsche 718 news and reviews
    MORE: Porsche news and reviews

    William Stopford

    William Stopford is an automotive journalist based in Brisbane, Australia. William is a Business/Journalism graduate from the Queensland University of Technology who loves to travel, briefly lived in the US, and has a particular interest in the American car industry.

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