Duncan Cowper’s Dax Rush Takes on Pikes Peak

“I am not Adrian Newey, I'm Duncan from Bishop’s Stortford,” says Duncan Cowper, a lime-plastering specialist from Hertfordshire. He may not be F1’s foremost car designer, but Duncan has stood close to the starting line of Colorado’s Pikes Peak race. Before us is the Dax Rush he designed, built and transported across the Atlantic to contest-for a second time-what is arguably the world’s most punishing hillclimb. And Duncan’s car... is not slow.

Duncan Cowper’s Dax Rush at Pikes Peak

Duncan has arrived at Pikes Peak in a machine that strongly resembles a Caterham, although it is actually a Dax. Dax was a UK sports car maker from Essex, now called JK Sports Cars, producing GRP Cobra replicas fitted with 8.2-litre V8 engines. In the 1990s, the company built several GRP kits, among them a Caterham/Lotus 7-style model named the Dax Rush. That is what Duncan drives. In a fashion.

The car uses a 500bhp turbocharged Suzuki 1300R Hayabusa motorcycle engine. Rear-wheel drive, sequential, light and exceptionally quick, it still appears to be a handful despite being detuned to 340–350bhp for the tight, tortuous Pikes Peak sprint. It does not even use anti-roll bars, relying instead on unusual-looking ‘camber compensation’ suspension: a web-like multi-link arrangement intended to keep the wheels flat regardless of load. Given its purpose, that is useful. Its brakes, meanwhile, came from Valtteri Bottas’ F3 car. Combined with Duncan-approved aerodynamics, it is an intoxicating home-built blend of the very best sort.

Photography: Olgun Kordal

From Hertfordshire plasterer to Pikes Peak competitor

That is precisely what Pikes Peak represents. So how did a UK plasterer make it here? Duncan’s tale is among the most unusual and life-affirming imaginable. He began as a mechanic building cars and hoped to become a welder, but qualifications were required-something that concerned him because of dyslexia. While managing those difficulties, he remained involved with the mechanical world, working for Dax as a shakedown and test driver before later establishing his plastering business. Along the way, he competed in club racing with his own car and assisted friends in preparing and running cars at assorted events.

This was far from ordinary equipment. Duncan helped at Geoff Page Racing, a specialist in Group B rally cars, turbo F1 machinery and countless other significant historic vehicles. He prepared cars for Goodwood, including Ayrton Senna’s Tolman and Rod Millen’s Tacoma and Celica-seriously impressive machinery. Yet it was one particular car that gave him the Pikes Peak obsession. Completely.

“One friend happened to have Ari Vatanen’s 405 Pikes Peak car that needed a shakedown and he asked me to do it at a local airfield. So of course I said yes! And the first thing that I did was lift my right hand up like a sun visor, obviously...” If you recall the celebrated 1988 Climbdance film, you will know exactly what he means. After racing-and winning with-his Rush, while building and rebuilding it for various events over the years, Duncan decided Pikes Peak was the target.

Building a Dax Rush for the world’s toughest hillclimb

“I was told I’d be better off building a car just for Pike’s Peak,” says Cowper. “But that wasn’t the point. I wanted to do it in my car. If you get it, you get it.”

What came next sounds almost unreal. Rod and Rhys Millen became his Pikes Peak points of reference-recommendations akin to royal approval-and friends, colleagues and acquaintances scraped together a tiny budget. There were highs and lows, wing-and-a-prayer moments, failed engines and every kind of setback.

But Duncan Cowper does not appear to understand failure. In 2024, he was second only to Romain Dumas’ 2,000bhp SuperTruck in the second practice sector. He finished third in the Unlimited class and ninth overall: a top-10 result for a plasterer from Bishop’s Stortford, in a car he built himself, at one of the world’s most demanding hillclimbs.

The finest part, however, is not even the car or Duncan’s genuinely remarkable speed. It is that passion and determination, backed by a budget of hope, cobwebs and a great deal of friendship, got them there. For an inspiring story and the authentic spirit of motorsport, few can surpass Duncan Cowper, the Hertfordshire plasterer, and his small Dax Rush.