The specialist: Swindon Powertrain

By Paul Hardiman

| 30 Jun 2026

Classic & Sports Car – The specialist: Swindon Powertrain

If anybody knows how turbulent and unpredictable the classic car industry can be, it’s Raphaël Caillé.

Luckily, the enthusiastic CEO of Swindon Powertrain knows how to drive his business in the right direction – and that’s with a lot of revs. Eleven thousand, to be precise.

That’s the redline for the Tuthill Porsche 911K, whose 3.1-litre flat-six uses Swindon Powertrain’s cylinder head.

The bonkers restomod is a showcase of the Wiltshire firm’s 24-valve unit, which is compatible with the air-cooled motors of 964- and 993-generation 911s.

For engine builders brave enough, Swindon Powertrain’s £31,447.50 (plus VAT) M24 cylinder heads have what it takes to reach 12,000rpm.

Swindon Powertrain’s 24-valve, cylinder-head kit can raise the Porsche M64 flat-six’s redline significantly

But when Classic & Sports Car visited Swindon Powertrain in 2020, the company had just developed its first HPD E Powertrain, a 107bhp ‘E-axle’ to replace the Mini’s A-series ‘four’.

At the time, the electric-conversion market was booming and Raphaël predicted more than half of the business’ output would be related to battery-powered classics within a few years.

“That did happen,” he explains. “In 2022, the majority of our turnover was from electric powertrains, but it’s switched back since then. Now we’re doing 70% internal combustion and 30% electric.”

Swindon Powertrain’s Porsche cylinder-head kit has been used in cars like the Tuthill 911K

Instead, the restmod scene has exploded. “That’s now where we play a key part,” says Raphaël. “We can make engines that deliver performance and emotion.”

That’s on top of creating a British Touring Car Championship-winning Hyundai motor and a V8 for Toyota’s assault on Australia’s Supercars Championship.

Swindon Powertrain has form when it comes to spectacular, high-revving engines: in 2020, it created a 24-valve, 10,500rpm Dino motor for a Stratos rally car, refining a concept Lancia started four decades ago, which fell by the wayside.

Motorsport has always been fundamental to the firm. “We need to do motorsport at Swindon Powertrain,” says Raphaël. “It injects passion.”

All of Swindon Powertrain’s precision metal machining is computer-controlled

The company was formed as Swindon Racing Engines in ’71 by John Dunn, to rebuild units to a consistent standard for Cosworth, first the FVA then the DFV. By 1975 its DFV was making 465bhp, taking five poles and eight Formula One wins.

Gary Dunn ran the company through the ’80s and ’90s, branching into touring cars, rallying (and the Vauxhall ‘red top’), plus head work on 14,000 John Cooper Works Minis, until the 2008 financial crash.

In 2009 Caillé bought the company, renaming it Swindon Powertrain in 2015.

There are 25 staff working on the original site in Swindon, plus five at Swindon France, near Orange.

Parts are manufactured at Swindon Powertrain’s base in south-west England, including camshafts

The emphasis has shifted from engine-building to design and manufacture, using simulation software packages, CNC machines and 3D printing.

“The seven-axis machines mean we can manufacture all our own components, including camshafts and crankshafts,” points out Caillé. “There are two dynos and various test rigs.

“Companies come to us with drawings and ask us to make components for them.”

Swindon Powertrain has helped Nick Swift to evolve his giant-killing Mini engines: “Nick wanted to increase the maximum revs again, but he had problems and asked us to develop a design that could cope.”

Swindon Powertrain’s expertise extends to the production of made-to-order wiring looms

More recently, it’s branched into electrics, with bespoke wiring looms made on site.

A recent 911 project required the team to reverse-engineer the Porsche’s loom, then make it lighter and more robust.

The firm has also been a Bosch Motorsport distributor for more than a decade and it’s just added MoTeC – a producer of ECUs, data loggers, lap-timing systems and more – to its portfolio.

Caillé has a grounding in competition and a love for all things with engines: “I initially worked in France for Citroën Sport on the Dakar Rally, then on the engines for the Williams Renault Laguna Super Tourer.

“I moved to the UK in 1998 to work for Triple Eight Race Engineering on the Vauxhall BTCC cars.

“It’s now been 15 years since I bought Swindon Powertrain and I’ve learnt that making predictions is challenging.

“If you asked me in 2020 I would’ve said the future is electrification.

“I still believe that is what is happening in the wider transport industry, but for us there’s still an appetite for great-sounding engines.”

Images: Max Edleston/Swindon Powertrain

The knowledge

Name Swindon Powertrain
Address Crampton Road, Swindon SN3 3JJ (and 30330 St-Marcel-de-Careiret, France)
Specialism Engine design, simulation, manufacture and testing; electric powertrains
Staff 30
Hourly rate £96
Tel 01793 531321
Web swindonpowertrain.com