Unless you're lucky enough to come from the world of single seater or prototype racing, driving a Radical at speed requires a complete reset. Everything you've learned before from road cars is no longer relevant and the laws of physics seem to have been turned on their head, such is the step up in performance. Yet despite this extremeness, there is real demand for road variants of Radical's output. Some people, presumably those with a screw or two loose, want their Le Mans Prototype-aping experience extended from the circuit to the high street. Which is like employing a Eurofighter for air mail service.
Okay, so that's not entirely true. Radical buyers are more often than not track day enthusiasts, so rather than a desire to annoy residents of Kensington and Chelsea by blatting past a mews in their open-cockpit featherweight, this demand for street legality is linked to more commendable reasoning. Getting to the circuit without a trailer, for example, or venturing out onto B-roads for an unrivalled visceral experience is another. The Rapture can be insured and taxed like any other road car, but it remains closer to a competition machine than pretty much anything else with plates, rest assured of that.
And doesn't PH know it this morning? With an ambient temperature of zero degrees and ice on the allotted B-road, the Radical is about as far from its intended operating window as it's possible to be in the UK. Aside from potential frostbite though, it's actually a remarkably docile place to sit. The 360hp and 320lb ft of torque 2.3-litre EcoBoost engine over the shoulder turns contently at 1,050rpm, the numbers on the race-spec digital display ahead are settled and the footwell heater keeps the toes alive. Make no mistake, there's a racing car underneath, but it's quite happy sat roadside a few miles from Brands Hatch behind our camera car. As is its driver, who easily fits into the wide, road-spec seat and harness while wearing a winter puffa jacket.
Ford's four-cylinder motor, tuned by Radical's engineers with new intake and turbo architecture, was chosen as much for its toughness as its performance. And in the 765kg Rapture, where it's fed by a centrally mounted intake that whooshes and gasps for air when the boost comes on, it's behaving almost exactly as it would in a series-run Ford. The gearbox it's linked to, a proper six-speed sequential controlled by paddles behind the tiny steering wheel, is similarly unfazed by the repeated requests for slow speed shifts. With neutral and reverse located one and two left paddle clicks down from first, and a foot clutch to pull away with, you're never caught fumbling for buttons. It's remarkably easy to operate.
There are, of course, some race car tendencies that are impossible to iron out. Lift off the throttle while driving in first and you'll be impersonating a nodding dog until you depress the left pedal. Pull away with too few revs and not enough slipped clutch and the engine will die in an instant. And attempt a tight manoeuvre at less than walking pace and the unassisted steering would defeat Samson. But once you learn how to more cohesively provide your inputs during low-speed progress - and to only attempt a turn only when rolling - there's no reason why you couldn't feasibly travel smoothly at normal road pace.
That's a brilliant feat in itself, because unlike most other track-worthy road cars, the Rapture's underpinnings were never intended for road use. It shares much with the SR8 prototype racer, and is built at the same Radical Peterborough home around an FIA-approved safety cell with an aluminium spaceframe attached. The composite body panels are near identical to those fitted to the SR8, while the front splitter is actually the same and the bi-plane wing is a slightly shrunken take on the 8's. More significantly, the underbody is the same, allowing the Rapture to achieve aerodynamic performance on par with its race numbered sibling. More on that shortly.
On the road, the effects of that motorsport base are inescapable. The Radical bobs and hops over bumps as if its suspension were solid, with the in-house-developed Nik-link suspension and adjustable dampers - even when set for road use - never allowing more than a few millimetres of body roll. It's less forgiving than even Radical's other road machine, the RXC supercar. As is often the case with racers, however, despite an inbuilt firmness the Rapture rides with a quality of damping that somehow stops it from ever feeling violent or harsh.
With nothing but an open roll bar and tiny deck of engine cover separating you from the exhaust, it sounds the nuts, all the time. Raspier and coarser than any performance road car, it's absolutely nothing like the motor in the Focus RS. Nor does it pull like it. 471hp per tonne ensures that throttle response isn't only immediate, it's also matched by a violent catapulting forward of car and driver from practically any revs above idle. On cold, damp tarmac the Rapture can be made to wheelspin in any of its six gears, but such is the effectiveness of the Quaife ATB limited-slip diff that forward progress is always to the fore. It doesn't bite like you might think.
Still, knowing that doesn't stop it from feeling every bit like an authentic racer when the harness is tightened, the helmet and race suit is on and you're peering over the pinky-sized windscreen, down the pitlane of Brands Hatch. Talk about a transformation in focus: the vibrations of the engine are suddenly indivisible from those rattling through your body. Like a race car, you feel at one with it almost immediately and no less serious about proceedings than the Porsche 911 GT3 Cup or Ginettas sharing the track.
The Rapture's three-second 0-60mph time is not representative of its true pace. Powering out and into the firing line of actual racing cars is not an act for the faint hearted, but such is the pace that you can work up the gears to the pneumatic fizzes of each shift that it's actually possible to arrive at Paddock Hill Bend and immediately fill the mirrors of the G40 that just flew by you. With this car wearing its Hankook semi-slicks rather optional track slicks also offered with the Rapture, the mechanical performance is available immediately, so you're not required to warm the rubber. Although reaching the car's peak so quickly is another question.
PH's first track stint in the Radical is best described by a single expletive. This is not a car a mere mortal can quickly get on top of - not because it's out to kill you, but because the limits are so exceptionally high that it requires continual increases in commitment before you feel like you're anywhere close to its potential. Only after a dozen or so laps in stint two is there the confidence to edge into the car's aerodynamic envelope. Passing the pit exit at 135mph as the wind pulls upwards on your helmet, hitting the unassisted brakes hard - and we mean with every pound of force your leg can provide - before tipping the car down Paddock Hill with barely a quarter turn of lock and getting straight back on the throttle, well, it's nothing short of mind bending. And organ shifting.
Still, the most enjoyable sensation in the Rapture at Brands is through Surtees, partly because unlike the rest of the track it's actually dry all the way through, but also because the chassis compressing effects of the airflow are most obvious. Brake where a pro might have lifted (or stayed flat!), and the chassis still hunkers into the surface so not even a glance of kerb can unsettle it, before being fired through the S bend, eyes wide like saucers. It's proper single seater stuff. And even when the aero falls away at low speed and you're left trusting in seat-of-your-pants feedback, the Rapture is a font of information. You soon build confidence to follow front axle push and mid-corner rotation with increasingly intense squeezes of the throttle. In a car with such explosive performance, that speaks volumes for the nuance it provides a driver with.
Predictably, stepping out of the Rapture is climbing off of a rollercoaster. Your body is suddenly not subjected to G forces from all angles and your head is out of the tornado. Which might be the worst thing about Radical's new machine: it leaves everything else with number plates feeling not just slow and heavy but numb and unresponsive. At £107,400, it's top end sports car money, but no conventional road car leaves you brimmed with quite so much adrenaline, and nor do many ask for a commensurate amount of commitment. To drive the Radical Rapture fast is to test your mettle, time and time again. If that's very much your brand of jam, it doesn't get any better than this.
SPECIFICATION - RADICAL RAPTURE
Engine: 2,262cc, turbocharged 4-cyl
Transmission: 6-speed sequential, rear-wheel drive
Power (hp): 360@6,000rpm
Torque (lb ft): 320@3,500rpm
0-62mph: 3.1 secs
Top speed: 165mph
Price: from £107,400