
- Patent images depict a Mazda sports car with a longitudinal four-cylinder.
- Mazda’s recent Iconic SP Concept premiered with dramatic butterfly doors.
- It’s possible the production Iconic SP could ditch the concept’s range-extender.
A pair of patents recently filed by Mazda have surfaced online, and neither one names the car they describe. What they do show is a small front-engined, rear-wheel drive convertible with butterfly doors, which narrows the field to two candidates.
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Mazda has made no secret that an all-new MX-5 is in the works, set to retain the same lightweight, gas-powered philosophy that has helped make the current model an all-time great. The company has also said it wants to build the Iconic SP concept. Either way, these filings make it clear that driver-focused Mazdas aren’t going anywhere.
Mazda/USPTO
The sketches, first spotted by Carbuzz, show a drop-top with a four-cylinder engine mounted longitudinally. The first filing focuses on the hinge pillar of an unspecified vehicle, illustrating how a front-engined, rear-wheel-drive car can use butterfly doors.
Read: Mazda Boss Confirms Next Gen MX-5, Says Will Continue With The Same Recipe
It outlines how Mazda engineers could bring the A-pillars closer to the shock towers to maximize chassis rigidity. The Japanese firm has never put butterfly doors on a production car, but it looks serious about making it happen. The document describes the arrangement as a flip-up side door, where the rear section swings outward and upward like a scissor or butterfly unit.
The same filing highlights ‘bracing reins’ that could be added to the car, helping to transfer load from the suspension mountings into that reinforced pillar, perhaps so hinges like these could work on a car with a convertible roof. It also describes an “apron frame,” a stamped-metal brace that links the front corners of the chassis to the firewall to further improve stiffness without adding significant weight.
Mazda/USPTO
The second patent covers the car’s crash structure and how external forces could act on it, channeling collision loads through the firewall, side sills, and toward the back of the vehicle to better protect occupants. Of greatest interest is that the drawings depict what appears to be a longitudinal four-cylinder engine and a traditional transmission tunnel, neither of which the stunning Iconic SP had, since it was previewed as a rotary range-extender.
What Is Mazda Planning?

All of this has led to speculation that Mazda may make radical changes to the next-gen MX-5, or perhaps put the Iconic SP into production with a four-cylinder engine. Since the MX-5 has always been about staying light and affordable, we’d be surprised if Mazda went to the trouble of engineering fancy new doors for it, and suspect they’re destined for the Iconic SP instead.
There’s also an outside chance Mazda is engineering one architecture to serve both cars, and that what these filings preview is the common platform underneath them rather than any single model.

Source: Carbuzz, US Patent& Trademark Office