As sports cars go, the current Mazda MX-5 Miata isn't too bad when it comes to fuel efficiency.

Okay, so at 25 mpg combined and 28 mpg highway it's a long way off the sort of vehicles we usually feature, but let's just say it's one of the best of a bad bunch.

That's not to say that it can't be improved upon. Well, with one of its predecessors, anyway.

An imaginative individual did just that, when he replaced an early Miata's 1.6-liter, four-cylinder engine with something rather smaller--a 1.0-liter, three-cylinder Suzuki engine, liberated from its old Geo Metro prison.

Spotted on the forums, a thread details the build process of the car, at the hands of Michigan-based user fujioko.

The concept was to build "a 50 mpg car that looks cool", and involved not only replacing the old engine with the new, smaller unit, but stripping out any unnecessary weight to give the car as little as possible to fight against.

The Suzuki engine and Suzuki Samurai gearbox already weighed around 200 lbs less than the old engine, but further mass was removed leaving a relatively spartan vehicle. And lighter though it was, with only around 50 horsepower to call upon, the Miata's already modest speed was cut further.

Economy improved though. Original Miatas were rated at 24 mpg, and on some journeys, fujioko's Miata was nearly doubling that--but a safe 40 mpg was in reach on virtually all trips.

However, the saga didn't stop there--while fujioko still appears to own the three-cylinder Miata, he put another project on the go--a Ford Festiva-engined 1.3 Miata.

With 63 horsepower the new project is virtually a rocketship compared to the Suzuki-engined one. Thanks to Mazda and Ford's collaboration throughout the 90s, the 1.3 is also fairly similar to the standard 1.6, making it an easy 'stealth' swap.

Less unusual than the 3-cylinder, fujioko describes the Festiva-engined car as "more user friendly", but gets an easy low-to-mid 40s miles per gallon, and 50 mpg is within reach on more sophisticated injectors.

A slower Miata isn't for everyone, but as we've seen so often before, resourceful individuals really can make virtually anything more efficient--throwing down the gauntlet for the big carmakers to do the same.

And if you don't like gasoline, there's always the electric Miata option...


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