How best to think of it? Well if you could rightly describe the 600LT as a road car with a lot of track performance built into it, you could equally think of the 620R as its mirror image: a car primarily intended for the track but which is not totally impractical and won’t drive you mad on the way there and back.
McLaren says it is not a development of the 600LT, indeed it was done by a completely different team. Instead the start point for the 620R was the 570S GT4 racing car which, having raced one, I can tell you is a rather more serious proposition. What McLaren has tried to do is create a road going version of that car and if you’re wondering why they didn’t just bolt some plates onto the GT4 and have done with it, there are two reasons. First, there are all sorts of homologation issues which would never allow it and, second, even if they did, the result would be absolutely horrible.
Horrible because you can’t run racing car ground clearance, suspension geometry and spring rates on a road car. So what McLaren has done is bring over or adapt those components that can be used on a road car, including the GT4’s passive dampers, each with 32 clicks of adjustment for bump and rebound. The aero package (including the adjustable rear wing) is very similar to the GT4’s, but with sharp edges rounded off to make them road legal. It has the GT4’s solid suspension top mounts and spring and roll bar rates as close to the racer’s as is sensible for a car used on road too.
There are various carbon bits inside, like the shift paddles, steering wheel spokes and centre console, but the 620R’s real rabbit out of a hat are its tyres. Or at least its optional tyres. As standard it comes with the same Pirelli Trofeo R rubber seen on the 600LT, and a standard P Zero and all season Sotto Zero are available too. Not much news there. But you can also run your 620R on slicks. Now of course there’s nothing to stop you bolting slicks to any car, but the 620R’s are bespoke to the car, unique in their blend of size, construction and compound and tailored precisely to suit the characteristics of just one car, and I know of no other car company that makes that offer.
And finally there is the powertrain which is nothing like the GT4’s and thank goodness for that because the racer is so inherently rapid, its motor has to be pegged back to something less than 450PS just to give the opposition a chance. The 620R is entirely uncorked, its 620PS providing acceleration so rapid that by 200km/h it is only 0.3 seconds behind the 100PS more powerful 720S.