McLaren has whipped the covers off the first-ever Sport Series model to wear a 'Longtail' badge, the track-ready 600LT.
Although they share a carbon MonoCell II chassis, almost a quarter of the parts on the 600LT are new compared to the 570S. It shows: the new Sport Series flagship tips the scales at just 1247kg in its skimpiest (dry) guise, undercutting the regular car by 96kg. You'll need to spec the full range of MSO Defined carbon parts (think vented fenders, for example) to hit that number, though.
Thank a carbon-fibre-heavy diet for those lightweight credentials: the increasingly-popular weave has been used for body panels like the front fenders, along with the standard sports bucket seats. If carbon is your thing, there's plenty of it here.
Power comes from a reworked version of the 570S's twin-turbo 3.8-litre V8 producing 441kW and 620Nm, breathing through a new top-exit exhaust system McLaren describes as "shorter and more extreme" than that of the Senna. Those figures are up on the 419kW/600Nm offered in the 'standard' 570S, and don't fall far short of the now-defunct 675LT's outputs of 496kW/700Nm.
Keeping all that power in check is an aggressive aerodynamics package encompassing a longer, taller rear diffuser, a fixed rear wing, and an ankle-breaking front splitter. It looks positively mean to our eyes, although you may disagree.
There are stiffer engine mounts, a unique aluminium suspension and track-ready Pirelli Trofeo R tyres to up the car's racing credentials, along with a quicker steering rack, sharper throttle and more capable brakes. Unfortunately, McLaren hasn't provided any performance figures or lap times to show how much quicker than the base car it actually is.
Given the base car hits 100km/h in a claimed 3.2 seconds, we'd suspect the 600LT will dip down to the very low threes – unless the wing and extra downforce limit the car's accelerative potential, naturally.
Behind the wheel, the standard bucket seats have been turfed in favour of carbon-fibre units nicked from the P1. If they're not extreme enough, buyers will be able to spec the lightweight torture devices from the Senna. Beyond that, the cabin is set apart from the regular Sport Series car with some two-tone trim and a stripe on the steering wheel.
There wasn't an abundance of over-the-top luxuries in the 570S to start with, making it tough to strip things out.
Production for the latest LT will kick off in October, and will only last 12 months. McLaren hasn't given an indication of how many will be made, but says build slots will be scheduled around existing Sport and Super Series cars, along with the Senna and BP23 Hyper-GT.
McLaren has confirmed the 600LT will be coming to Australia, we'll have to wait for pricing.