Wacky one-offs: the stories behind five track-day specials

In garages, workshops and sheds right across the UK, tinkerers and would-be mechanics get their fingers dirty.

Most undertake straightforward vehicle maintenance, while others restore bodywork or make running-gear modifications. A small number, however, squirrel themselves away for weeks at a time and only emerge once they’ve built something truly staggering. It might be a lightweight track car with two motorcycle engines, or a diesel supermini that’s faster than a modern super-saloon.

Welcome to the world of the one-off special – a world where people tend not to ask why but why not?

Seat Arosa drag car:

“You start off in second gear, engage the launch control system to hold the engine revs, then try to get the clutch release just right,” says Paul Lynas. “As soon as you let go of the clutch, it’s like being catapulted. That’s the only way I can describe it.”

Lynas is the driver of this Seat Arosa drag car, a Darkside Developments project. It was with him at the wheel that the Arosa recorded a quarter-mile time of 9.7sec at Santa Pod. It hit 60mph in 2.3sec and 100mph in a scarcely believable 4.8sec that day. For a while, it was the fastest front-wheel-drive diesel car on the planet.

Darkside Developments built this car to push the boundaries of what could be achieved with a four-cylinder diesel engine. The base unit is a 2.0-litre common-rail lump, uprated in just about every way imaginable.

With a Borg Warner turbocharger from a John Deere combine harvester, which boosts at an astonishing four bar, the engine develops 550bhp and 650lb ft. The exhaust runs right out through the bonnet and every time Lynas builds the engine revs, a thick, acrid plume of smoke bursts into the air like ash erupting from a volcano.

With all that power and torque being sent to the front axle alone, the Arosa demands plenty of skill on the part of its driver. It’s all about managing the clutch release, reckons Lynas, although he points out that on a treated drag strip, the slick rubber does find enormous traction. The Hoosier tyres are purpose-built for drag racing and they’re run at just 6psi. They’re so baggy, in fact, that once the car is up to speed, they expand in diameter by an inch and a half. As they grow taller, they also become narrower, which helps to reduce the car’s frontal area.



Five mad one-off creations to buy on the PistonHeads classifieds: 

SUBARU IMPREZA TURBO 2000 – A road-legal Time Attack car, this Impreza produces up to 700bhp. According to the ad, it was built over a five-year period with receipts totalling £60,000. It has anti-lag, just like a World Rally Car, and a billet turbo. Price: £25,000

VAUXHALL VXR8 – With 587bhp, the most powerful factory-specification VXR8, the GTS-R of 2017, was absurdly fast. Quite what a VXR8 with 705bhp must feel like is anybody’s guess. The seller reckons it’s good for 200mph and cost £60,000 to build. Price: £28,950

FORD MUSTANG GT – How much power can you get for less than £50,000? As much as a McLaren Senna, apparently. Modified with a high-capacity Whipple supercharger, this Mustang V8 produces 800bhp. The chassis has been uprated with KW coil-overs too. Price: £42,500

NISSAN 200SX – Described in the adas “a race car and not a show car”, this S15-generation 200SX has close to 500bhp and an aero kit to shame a Pikes Peak contender. Still road legal, it was built by Kent- based MnM Engineering. Price: £15,500

VOLKSWAGEN GOLF VR6 4MOTION MK4 – Having started life as a VR6 4Motion with 204bhp, this Mk4 Golf now has more than twice the output its maker intended. A Rotrex supercharger and various intake and exhaust modifications boost power to 412bhp. Price: £13,350

This article was originally published on 29 September 2018. We’re revisiting some of Autocar’s most popular features to provide engaging content in these challenging times.