The Ariel Atom 4RR has a higher power-to-weight than a Bugatti Chiron

Plucky Somerset sports car company Ariel has upped the ante again, in celebration of its 25th anniversary. Packing more power even than the screaming Ariel Atom V8 is the new Atom 4RR, a 525bhp, 406lb ft monster that is the most powerful car in the company’s storied history.

Nevermind being a long way from the K-series-powered Atom 1 that started it all, the Atom 4RR adds 125bhp, or more than the total power in an Atom 1, compared to the 400bhp Atom 4R on which it’s based. The last most extreme Atom that starred in our Track car of the Year test in 2024 was not a car that felt short on power or lacking in terms of power/weight… Assuming a similar kerb weight to the Atom 4R, the Atom 4RR should have a power-to-weight ratio of more than 800bhp/ton. In other words, higher than a Bugatti Chiron Super Sport

The 400bhp that the Atom 4R ‘makes do’ with is already a 30 per cent increase on what the K20C engine usually produces in Honda’s Civic Type R hot hatchback. It’s that same engine that’s been juiced up to a scarcely believable 525bhp here. How have they done it? Without going into the grainiest of specifics, Ariel claims the engine has received a ‘host of internal changes and new components’, with upgraded oil and fuel systems to keep it lubricated and fed. Further details of the Atom 4RR’s exact technical makeup are to be announced later in the year.

To appearances little has changed in terms of aero and set-up by comparison to the already extremely track-focused Atom 4R. It carries the same front splitter and formula-style rear wing as well as the enormous side pods, which on the 4R house an intercooler on the right and a cooling radiator on the left.

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A number of the incredibly pricey options on that car’s options list should by rights come as standard here, though as above the 4RR’s exact technical appointment is yet to be confirmed. Our picks would be the 12-way adjustable Bosch ABS and seven-stage traction control systems, remote reservoir Öhlins dampers with 23 clicks of adjustability and aggressive front and rear wings. Certainly, the AP racing CCM brakes and maybe even the lightweight carbonfibre wheels. The tyre options will no doubt be aggressive – the most potent tyre available for the 4R was Yokohama’s A052.

Just 25 Atom 4RRs are set to be built, one for each of Ariel’s bygone years as a sports car manufacturer. Since the beginning, Ariel has traded on that distinctive tubular space frame chassis design, sans bodywork and weight-adding creature comforts. The power of the 4RR might be quadruple that of the original Atom and it may be clad in all sorts of aero accessories and cooling apparatus but it’s still unmistakably an Atom.