What is it?
The fastest closed McLaren ever made. If you want a quicker one, you’ll need to talk to the F1 team. It is a Senna designed without regard for road car regulations or race car rules. In that regard therefore, this is the clearest vision of how McLaren would actually like the Senna to be.
There is, of course, much that they share: the same basic tub, engine and transmission for instance. But so too is the GTR wildly different. Take the body: it has a completely new front splitter and rear diffuser, with additional dive planes on the front and vortex generators on the side. But you’ll notice more the outrageous rear wing, positioned far more rearward where it would be completely illegal on the road but where it can work far better with the diffuser on the track.
The car is 34mm lower than a Senna, 77mm wider at the front and 68mm wider at the rear. All this allows the GTR to match the Senna’s downforce at lower speeds with less drag and, ultimately, deliver a full tonne of downforce at 155mph, 200kg more than that provided by the Senna which already broke new ground in this regard for a road car.
Because it will only ever be driven around a race track there is no need for the clever but complex and heavier height adjustable suspension used on the Senna, so it’s ditched and replaced by a lightweight conventional system based on the racing suspension developed for the 720S GT3 race car.
The engine gets its own mapping and loses its secondary catalyst, which is why it is able to develop 814bhp, a rise of 25bhp over the road-going Senna and taking the engine past the 200bhp per litre mark.
The interior is that of a pure racing car – pared to the bone, and all major controls are mounted on the sawn-off steering wheel where they can be reached without stretching (not possible when you’re clamped by a six point harness) and operated easily by a gloved hand.
Strangely, it is only 10kg lighter than the Senna, though at 1188kg dry it is the lightest McLaren coupé since the F1. The weight lost by the simpler suspension, stripped interior the removal of the catalytic converter and its airbags is almost entirely offset by the additional bodywork, data logging systems, the on board air-jacks and fire extinguishing system. It costs £1.1 million before tax.