JCB Hydromax Hits 406mph at Bonneville — and Hands Hydrogen Combustion Its Proof Point

When we covered JCB’s return to the Bonneville Salt Flats, the target was 350mph. The team has now comfortably beaten it: the hydrogen-powered JCB Hydromax has recorded a two-way average of 406.320mph across the Utah salt, making it officially the fastest hydrogen-powered car in history — and the fastest zero-emission car of any kind.

The record, overseen by the FIA and still awaiting final ratification, required two runs through the measured mile within an hour. Hydromax posted 400.623mph on the outward leg and 412.135mph on the return. Behind the wheel was Wing Commander Andy Green, who knows something about salt-flat mathematics — he has held the outright land speed record of 763.035mph since driving the jet-powered ThrustSSC in 1997.

Combustion, not fuel cells

The significance for the energy sector is in how the speed was achieved. Hydromax is not a fuel-cell electric vehicle. It runs a pair of JCB’s own hydrogen internal combustion engines — the same fundamental technology the company has been developing for its construction machinery — heavily reworked for the record attempt and driving all four wheels, which puts Hydromax among the fastest wheel-driven vehicles ever built.

The engineering supply chain reads like a roll call of British specialist firms. Ricardo took on the engine development, lifting output of each turbocharged unit from its standard 74bhp to a startling 800bhp. Prodrive, the Banbury motorsport outfit, built the car and ran the Bonneville operation. Xtrac designed and manufactured the six-speed paddle-shift gearbox. The clutches, fittingly, came straight from a JCB backhoe loader — the only components available that could withstand the torque.

The record run came days after a shakedown at Bonneville’s Speed Week, where the car ran under Southern California Timing Association rules with output pegged back to 1,200bhp and still managed a one-way best of 368.347mph.

A deliberate echo of Dieselmax

JCB has run this playbook before. Twenty years ago the company took Dieselmax to the same salt flats and set a 350.092mph record to showcase its diesel engine technology. Repeating the exercise with hydrogen — and adding more than 50mph in the process — is a calculated statement: that hydrogen combustion is not a stopgap but a serious, high-performance branch of the energy transition.

Green called the record “a huge achievement by a world class team and superb technology.” JCB engineering director Ryan Ballard, who has led the project since it began in February 2025, credited the engineering team and noted the car delivered exactly as prepared.

What it means for the sector

Hydromax’s number is more than 60mph clear of the fastest electric car ever — the Buckeye Bullet 3, which averaged 341.264mph at Bonneville in 2016. Hydrogen combustion does produce a small quantity of NOx alongside its water vapour, so “zero emission” carries an asterisk that fuel cells don’t. But for heavy industry, the appeal has never been about outright purity: it is that hydrogen combustion engines can be built on existing engine manufacturing lines, serviced by existing engine skills, and dropped into machinery where batteries and fuel cells struggle on cost, weight or duty cycle.

As we argued when the attempt was announced, the record itself is the headline, but the durable story is the supply chain and skills base it demonstrates. A British OEM, three British engineering houses, and a hydrogen powertrain running at better than 400mph: for the engineers, technicians and project leaders weighing up where the energy transition’s careers will be, that is a rather persuasive advertisement.

Image courtesy of JCB.