As a few lucky turkeys breathe a sigh of relief that they weren’t the ones to get eaten, and blurry festive memories fade for another year, I am left with 50 bags of rubbish, crates of empty booze bottles, a traditional Christmas cold and a hole in my pocket the size of Santa’s belly. So thanks, everyone. No, really . . . it was a joy. It may have been more of a wet Christmas than a white one, but hey, you can’t have it all.

I was joined this year by my parents, who — incredibly — happily exchanged Barbados for Billingshurst to be with me at Christmas for the first time in years. Nobody cooks a roast dinner or stuffs a Christmas stocking quite like my mum, so I was delighted at their visit, though perhaps even more so because it gave me the chance to scare the life out of my dad.

Jumping at the opportunity to accompany me on my first test drive of the Ariel Atom — the minimal sports car with race-bred construction that you see here — he really didn’t know what he was letting himself in for. And to be totally honest, neither did I, as I’d never driven anything quite like it. As it weighs little more than 1,000lb (half a Ford Fiesta, a fifth of a Bentley Arnage), this two-seat pocket rocket has the power-to-weight ratio, and therefore the performance, of a motorbike.

If you consider that five years ago, when my father left England to live in Barbados, I didn’t have a driving licence, and add that fact to the Atom’s apparent flimsiness, with hindsight I can easily understand why Dad was feeling a little uneasy. His only memories of my driving were probably of when I was in charge of a tricycle. Or maybe he remembers taking me for my first round of golf, when I rolled the cart into a bunker and was subsequently banned from the Royal Westmoreland golf club, aged 13.

Either way, Dad had good reason to be twitchy. It must have been like going for a spin with Rowan Atkinson at the wheel and not being able to get visions of Mr Bean and his yellow Mini out of your head — slightly worrying.

Unbeknown to Dad, since my success on Top Gear (when a lap of the programme’s circuit took me to the top of their celebrity leader board) I have been training regularly for my international racing licence. When verbal offers came in from Maserati to compete in their Trofeo single-make racing championship, and when I’d heard mention of an all-women’s team at Le Mans, I felt it was time to take it seriously and see if I was up to the task.

Although I had done a lot of road driving, including two Gumball rallies across America and a supercar run through Europe, I hadn’t done any track work, so I needed to put in some serious hours. I started with a trip to Modena with Maserati for an advanced driving course. This was followed by a Club Fiorano outing, driving Ferraris at Goodwood as part of Dr Fox’s Help a London Child day, which really whetted my appetite.

Then it was time to take my Association of Racing Drivers’ Schools licence under the guidance of my instructor Joe Macari, which I did this summer at Goodwood. The next step is to finish 12 races and get a signature after each one, thus completing qualification for my international racing licence. I hope to start doing that in the spring.

In the meantime I’m trying to practise in as many different types of car as possible. At the moment I’m attempting to master the Audi RS4, which I absolutely love, although ironically I’ve found that a Suzuki Liana can be just as much fun by being even more of a challenge.

My dad had gone white by the time I’d driven him to the end of the drive, but in all fairness to him, as the Ariel is so minimal that it doesn’t even have a windscreen it might just have been the cold air sapping his colour. I did contemplate pulling over and twisting the clever gold knob that adjusts the suspension so as to make the trip down my bumpy driveway a little more comfortable, but I was too anxious to get this car on the open road.

We were both fascinated with the lack of everything you might normally expect to find on a car. For a start there are no doors, and there’s no windscreen or roof either. But the Atom also has the rather unusual distinction of having no body panels, so you can watch the suspension and steering work as you drive.

Of course, the lack of body panels saves a lot of weight and consequently the Atom’s power-to-weight ratio exceeds that of a Porsche 911 Turbo, a Ferrari Challenge Stradale or the Lamborghini Murciélago. And as if this wasn’t enough, tuning packages are soon being released to take the Atom’s Honda engine to over 280bhp and a power-to-weight ratio not far short of 600bhp per ton.

“How fast are we going — a hundred?” shouted my father.

“Only 55, Dad,” I replied. Although I must admit that it did seem quite a bit faster.

My face was starting to contort and I found that even in third gear it was difficult to breathe properly. Either the Atom needs a windscreen or its occupants should wear full-face crash helmets.

Ariel has been producing grand prix cars since 1898, and is therefore one of the oldest marques in British motoring history. The Ariel name is best known for motorcycles, but the bikes alas are no longer.

Having returned home for some crash helmets, I noticed Dad was finding it hard to get out of the car. Unsure whether this was because he is 6ft 5in and was nervous at the time, or if it was due to his having eaten too much Christmas turkey, I left him to it and collected the skid-lids.

The disadvantage of wearing a helmet, as I found out, is that you don’t quite get the full experience of the wonderful engine noise the Ariel makes. But at least you can breathe.

On the track I found the six-speed gearchange smooth and easy, and although the brakes were a bit spongy until warmed up, I felt confident at the wheel after just one lap. When cornering at speed the Atom would start to understeer, but in a very controllable and predictable manner, so it was easy to balance the little car through bends on the throttle without any nasty surprises.

Whether it’s because of a lack of cocooning bodywork, or due to its proximity to the ground, the Atom seemed mind-blowingly fast — like a go-kart that has been on a fat dose of steroids and has grown up. What a blast! I was having so much fun I’d forgotten about my poor old dad, who by this stage was silently gripping his seat so tightly he seemed to have become a part of the single-piece moulded composite.

While this car is totally road-legal, it feels as if it shouldn’t be, and is a world away from ordinary road cars. The view along its nose is pure single-seat-racer stuff, and the scant instruments are housed in a pared-down console. The one-and-a-half-turn steering rack is competition derived and the alloy pedals adjust for height, just like in a real racer.

The manufacturer’s claimed 0-60mph time of 3.7sec puts the mighty Atom in the very premier league of performance cars. Its engine is a 2 litre Honda iVTEC unit from the Civic Type-R, so it should be reliable too.

The astounding thing is that this bundle of pure excitement and performance is produced in a tiny Somerset village by a company with a staff of just five. Even when they move to a new factory later this year and launch a new model they are unlikely to make more than 100 cars a year.

Simon Saunders, the man in charge, says he builds the Atom to “give the thrill of a single-seat racing car or motorbike while remaining safe, legal and practical”, and without doubt he has succeeded in his aim. It may not be the best car for taking on a touring holiday in France, but this little gem can embarrass most high-performance cars on the road, and at only £24,000 that makes it great value for money.

So thank you, Simon, for my unexpected Christmas present; it looks so good in my garage that I really think I should keep it.

VITAL STATISTICS

Model: Ariel Atom 2
Engine type: Four-cylinder, 1998cc
Power: 220bhp @ 8200rpm
Torque: 145 lb ft @ 6100rpm
Transmission: Six-speed manual, rear-wheel drive
Suspension: (front and rear) double wishbones, inboard dampers and coil springs
Tyres: (front) 195/50 R15 (rear) 225/45 R16
Top speed: 145mph
Acceleration: 0 to 60mph: 3.7sec
Price: £24,000
Verdict: No-compromise racer that's a hoot to drive

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