Driving coach Rob Wilson talks about racing “becoming a craft” when you get good at it. Once you understand the physics of driving, what will make a car fast and what won’t, you can work on this craft, patiently, to go quicker.Which is fine if, like Wilson, you’re a driver who’s competed in Nascar, at Le Mans or around Daytona, or you’re one of the drivers – up to and including those in F1 – who have called on his training. What happens in microseconds can become a craft if you’re equipped to deal with it.

And if you’re not quite up to speed? Welcome to the Citroen C1 Racing Club.

The C1 Racing Club was born, if not out of frustration with, then as a result of, the modern limitations of Citroen 2CV racing. It used to be one of the cheapest forms of motorsport around but even the newest 2CV is decades old these days, and running and maintaining a race example is getting – by hobby standards, if not by those of motor racing – expensive. So a few devotees decided they’d put a C1 together instead and see how it went as a racing car. Slowly, was the answer. But cheaply. So here we are.

You’ll know the C1. Or you’ll have seen it. Mechanically identical to the Peugoet 107 and Toyota Aygo (though the club only allows Citroens in for now), it’s a city car, built from 2005 onwards, which could be had with three or five doors. The Club uses the 3dr version and alterations to turn it into a bona fide race car are limited. The phrase “no modifications” features in the standard regulations no less than 15 times.

Sure, every car can be stripped of its interior trim and carpets, but mostly only so that safety equipment can be fitted. The dashboard, including a working radio and handbrake, must be retained. The wiring loom, engine, exhaust, gearbox, glass and even window winders have to be as standard, and each car must be MOT’d. There’s a minimum driver-aboard weight limit of 910kg, which most drivers will add ballast to get up to. Power, wait for it – and you’ll have to – is 68hp, delivered to the front wheels via a five-speed gearbox, the fifth gear of which you’ll probably never need on a race track. No, you can’t modify the engine. No, you can’t mod the intake. No, you can’t remove the catalyst.

What you can – and will – do, is make a few changes to the suspension, shimming the rear to adjust toe angle, fitting strut braces if you like, and adding a club-supplied lower front wishbone, which puts more rubber to the road; although again, the terms are relative.

Does it all sound suitably daft? It might, but the idea has struck an uncanny chord. The Club had its first races this year, and already there are more than 80 cars completed or in-build. Because, all-in, you could be looking at having a fully-prepped racing car for under £3,000. The Club recently announced a 24-hour race at Rockingham next May. A week later, the grid was full, after 70 cars had signed up.

Sounds like a lot, does it not, 70 cars around Rockingham? It probably is, but then, it is manageable. And I know this because last week I climbed into a racing C1 at Spa Francorchamps, alongside 107 other cars – around half of them 2CVs or curious derivatives thereof, another half or so C1s, and a couple of old Minis – and we all fitted. For 24 hours.

This remarkable feat is, I suspect, because the speed differentials are not that huge. Unlike classic endurance racing, where an LMP1 car may well be on circuit with GTE cars, or Britcar where a Ferrari F430 might be on track with a Volkswagen Beetle, the C1 and its ilk are all similarly, well, how to put it … slow.  An F1 car will lap Spa in around 1m 46s, at an average speed of 147mph. A C1 can only dream of 147mph, and wants almost two minutes more to complete a lap. An average of 75mph, then, would have a C1 writing postcards home. So there is time to think about what you’re catching, or what is catching you, and that makes 108 cars fit into 4.3 miles quite easily.

And, now I read it again, an average of 75mph over a lap doesn’t sound so bad, does it? It sounds, dare I say it, exciting. Dear reader, it is.

It doesn’t matter how thrilling a road car is, racing at Spa in the dark, even with 68hp, is absolutely brilliant. At one point I was talking to two blokes, who between them have three Porsche Carrera GTs, and they thought it was pretty exciting too. I drove for two hours from dusk and it was – and I kid you not, here – one of the very best drives I’ve ever had in 20 years of writing about cars.  What is the car like? It may not be very quick, but turning in to Eau Rouge at 90mph in the dark and the rain, with wipers smearing water relatively ineffectively across windscreen oil and filth, only a few inches from another car, it all felt real enough to me. Besides, the suspension changes mean that there’s some chassis adjustability to the C1, too. The steering remains pretty uncommunicative, the brakes are superb, the gearshift light and the engine revvy. And even on a big, senior circuit, it’s great fun. There are places at Spa where you have to take a deep breath before turning in flat, places where you have to brake heavily, and places where – obviously – your foot is pressed so hard to the floor that you emerge from a stint with an aching right calf.

I shan’t bore you with how I got on, suffice it to say we finished mid-class and I didn’t put a dent on it, which I always count as a decent day’s work.  But two things stand out for me: one, is that Rob Wilson was right, and that driving is a craft – you have a lot of time to consider how right or otherwise you’re getting it behind the wheel of a C1. The other is just how much fun this unlikely racing car is, to the extent that my old VW Baja Beetle will shortly be for sale, and that I intend to find myself part of a very large C1 racing grid next year.