Seen in concept form at the Geneva motor show, the Senna GTR is now headed for production, and with testing started, McLaren is starting to share a few details of its most focused car yet. First off, the car is reckoned to generate as much as 1,000kg of aerodynamic downforce at speed, which effectively all but doubles the weight of the car, pressing the Pirelli slick tyres ever harder into the track surface. The brakes are also uprated, and with the tyres and aero working full-tilt, can provide a whopping 3G deceleration.
The Senna GTR will also get wider-track suspension, with components pinched from the GT3 racing version. The all-carbon bodywork gets bulged wheelarches, huge splitter at the front, a rear diffuser, and a re-worked version of the standard model's active rear wing.
There's also a massive diffuser under the rear end, and the airflow through that is coupled to the airflow over the wing for even greater efficiency and downforce. The aerodynamic package has also been optimised to reduce the car's sensitivity to yaw (as when you're turning a corner) and also to pitch (as when you're braking). As McLaren points out, the aero package is so sophisticated and clever that it actually wouldn't be allowed on a proper, homologated, racing car. Talk about the unfair advantage...
Weight has been pared back from the already-light Senna, thanks to the binning of the airbags, the infotainment system, and the folding digital dashboard display that you'll find in the road car. The steering wheel is also specific to the GTR, and is a lightweight item with integrated gearshift paddles. The only concessions to luxury (and active safety) are air conditioning (well, you're going to get sweaty throwing this around a racetrack) and a radar-assisted, rear collision avoidance system - presumably to protect you from ham-fisted trackday novices caught out by the Senna's immense aero-assisted braking capability.
The 4.0-litre twin-turbo engine is the same as that found in the road-going Senna, but it gets an extra 25hp for a total of 825hp, while torque climbs to 800Nm.
Only 75 Senna GTRs will be built; they're all left-hand drive only; they'll cost €1.25 million each (before tax); and they're all sold out already.
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