Mazda MX-5 Keiryo: the Miata capable of matching a Ferrari F40 in power-to-weight

Rocketeer pushes the iconic Japanese roadster to the limit with an extreme build delivering 375 hp and just 850 kg, a combination worthy of a true supercar.

The Mazda MX-5 has always been a benchmark for pure driving enjoyment, but it is also one of the most versatile platforms for radical tuning projects. This is precisely the territory of Rocketeer Cars, a British company renowned for reimagining the Miata with far more ambitious powertrains. Its latest creation is called Keiryo, which means “lightweight” in Japanese–and the name is entirely justified. This modified MX-5 boasts the same power-to-weight ratio as a Ferrari F40, instantly placing it in a completely different league.

A supercar-level power-to-weight ratio

Rocketeer claims the Keiryo delivers 375 hp while weighing just 850 kg, resulting in an astonishing 441 hp per tonne, figures typically associated with machines such as the Lamborghini Huracán V10 or the McLaren 620R. From an engineering standpoint, this philosophy echoes the purest spirit of motorsport and the relentless pursuit of weight reduction seen in modern Formula 1, where every kilogram matters as much as outright power.

At the heart of the Keiryo is a heavily reworked 3.0-litre naturally aspirated Jaguar V6, rebuilt and strengthened by Rocketeer to extract significantly more performance than standard. The company has not yet disclosed exactly how it achieves such a low kerb weight, but extensive use of extreme lightweight solutions is a given. The first customer car is already in production, with delivery scheduled for early next year, confirming that this is far more than a theoretical exercise.

Exclusivity is another key pillar of the project. Rocketeer plans to build just 10 examples of the Keiryo Miata, while also offering a less extreme Touring version that reinstates “certain comforts” absent from the hardcore variant. This suggests that the Keiryo sacrifices much of the MX-5’s usual equipment in favour of raw performance and driving purity–a philosophy that is becoming increasingly rare in today’s market.

In parallel, the British firm is developing a Mk.III (NC) version of its Rocketeer RestoMod, with the first unit nearly complete and set for delivery in early 2026. This model will feature a revised V6 producing 300 hp and 360 Nm of torque. For a company that has built only a few hundred cars in almost a decade, the Keiryo stands as its crowning achievement and a powerful reminder that the Mazda MX-5 remains one of the most versatile and captivating sports cars in the world, even capable of standing shoulder to shoulder with legends like the Ferrari F40.