There was a moment, right after passing the 140mph mark on Bruntingthorpe's back straight, when I began to realise just how far the Sin R1 road car has come in its short life.
I last saw this V8-engined, 444bhp sports car at Autosport International in January and, to be honest, was a little disappointed not to see a finished product. With the R1 racing car already finished and ready to race in the GT Cup, I'd expected to see the full R1 road car ? but instead the firm showed a hollow prototype, a body with no engine or interior.
Nevertheless, nine months later an almost-complete car is hurtling around the Leicestershire aerodrome. I say ?almost-complete?, because although orders are being taken this is still described as a pre-production model. It's about 95 per cent there, Sin boss Rosen Daskalov tells me. The interior, mechanicals, shape and panels are as customers would see them. What remains is to lift the fit and finish.
There's some work to do in that area, because although the R1 looks very striking on the road, close inspection reveals some panel gaps which are too large, an uneven paint finish in places and carbonfibre trim which looks pasted on.
It'll all need attention if Sin wants to succeed in attracting the kind of clientele who have £72,000 to spend on a sports car. That?s high-end Jaguar F-type and Porsche 911 Carrera money, after all.
The real proof of the car's potential, though, is in a passenger lap. I'm told the R1's Michelin tyres have already been put to good use on a cross-continental dash from Bulgaria, where the Sin company is based. Not helping is the British weather, and Bruntingthorpe is seriously wet by the time we head out.
Getting over the R1's high door sill takes finesse, but once strapped into the relatively spartan cabin the visibility is more than adequate. Though narrow, those leather sports seats are comfortable, too. Driver Jonny MacGregor straps into the other side, and as we head towards the circuit he explains this is the first time he's ever driven the R1 road car.
The 6.2-litre V8 engine's sound fills the cabin ? more so than in other similar cars, it has to be said. There may be some sound deadening work to do here.
Soon enough we're on track, and it's clear what chief executive Daskalov and his team have spent their time doing. The R1 feels smooth and comfortable, even as we enter triple-digit speeds.
MacGregor works the six-speed manual transmission hard, and it seems a little notchy at first, but the car's response and handling appear to be pitch perfect. Later Daskalov tells me he rarely uses first gear as it?s so short, and instead pulls off in second.
On the back straight the R1 hits 140mph with no trouble. It almost feels lazy, effortlessly cruising along, but I'm reminded that earlier in the year we hit the same speed here in an old £500 Jaguar XJ Sport. There?s some dancing about from the front end and lots of wind noise, but from the passenger seat it still feels impressive.
A specific type of customer will be interested in buying an R1. With the racing version helping to raise brand awareness, there'll be those who can not only afford to buy the model, but who like the idea of owning truly rare sports car.
Plus, it has to be said, getting a project from hollow shell to full sports car in nine months is an achievement, especially for a small group working out of both the UK and Bulgaria.
The first cars could be ready for customer deliveries at the end of the year, leaving the team ample time to work out the final kinks. If they succeed, R1 owners could end up with a car capable of fulfilling its promise of offering supercar thrills at sports car prices.
Read more about the Sin R1
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The cabin of the McLaren P1 GTR has been revealed for the first time as the Woking-based manufacturer continues to develop its track-focused, limited-edition hypercar.
Using the (slightly) more road-oriented McLaren P1 as a base, the cockpit has been stripped out, with a greater focus on driver engagement and weight saving, albeit without compromising comfort or safety.
A new steering wheel based on the item used in the MP4-23, McLaren's 2008 Formula 1 car, is exclusive to the P1 GTR, which was first revealed at the Pebble Beach Concours d'Elegance in August.
Key controls are located to the centre of the wheel, allowing the driver to fully adjust the set-up and characteristics of the car without having to take their hands from the wheel. The DRS and IPAS buttons for the Drag Reduction System (DRS) and Instant Power Assist System (IPAS) are retained on the steering wheel.
McLaren says it has configured the controls so they can be comfortably operated when the driver is wearing a full race suit, helmet and gloves.
The cabin is equipped with lightweight carbonfibre seats similar to those used in DTM touring cars and full six-point motorsport harnesses. These will be set up for each P1 GTR owner, and mounted directly to the chassis, reducing weight by having no additional mounting brackets. The seats are compatible with a Head and Neck Safety (HANS) device.
Unlike some stripped-out track cars, the air-con system is retained in the P1 GTR to maintain comfort during track driving.
The carbonfibre MonoCage chassis is carried over from the road car, and weighs 90kg including the upper and lower structures, roof snorkel, engine air intake cavity, battery and power electronics housing.
The development programme for the car has focused on testing the capabilities of the upgraded powertrain, optimising the balance and handling characteristics on the car's Pirelli slick tyres, and working through aerodynamic developments including the fixed-height rear wing.
Company officials reported: "All tests were completed with results meeting or, in many cases exceeding, the stringent targets set. The McLaren P1 GTR development continues its rapid progress, with further mileage scheduled over the winter throughout Europe".
McLaren has now switched the focus of its testing with the P1 GTR to extremely hot conditions, taking its latest development prototype to the Bahrain International Circuit.
The British company has also revealed more details of its P1 GTR Driver Programme, which will teach owners how to get the best out of the car.
P1 GTR owners will gain access to areas of the McLaren Technology Centre in Woking that are off-limits to the public, including the company's racing simulator.
Paul Mackenzie, McLaren P1 GTR Programme Director, said: "Before they get out on track, each driver will join us at the MTC and have unprecedented access to the cutting edge facilities.
"This will enable drivers to build up a greater understanding of the car?s capabilities and true performance, as well as learning the braking and turn-in points before they arrive at the circuit. It also allows them to analyse and discuss their performance ahead of testing themselves in the real world situation, so they are fully prepared when they take to the track.
"It is a programme that has been developed over the years for our Formula 1? and our young drivers. It?s not just about fitness, but also about mental preparation, and looks at the full wellbeing of the driver, and prepares them mentally and physically for the activities they will experience on track."
McLaren P1 GTR owners will take part in six track events during the first year of the Driver Programme. The events will take place at "iconic racing Formula 1 circuits across the world".
At each event, drivers will have a dedicated race team responsible for running the car. This will include a personal driver coach and head engineer, who will work through telemetry and video analysis to hone skills, and optimise lap times.
The car, revealed at the Pebble Beach Concours d?Elegance, will go on sale in just under 12 months after production of the standard P1 ends. It will only be offered to the existing 375 P1 owners and will cost £1.98 million.
Watch McLaren's official video explaining its P1 GTR Driver Programme:
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