The Mazda MX-5 has never been about outright speed, but cram in the LS7 V8, and then the little roadster will get really fast. Owners of the fourth-generation Miata in the Hardtop Retractable Fastback specification have documented its build on YouTube, culminating in shooting video on the Autobahn with RF at full tilt. While a standard car will do around 140 mph (225 km/h), this little beast manages to hit 187.4 mph (301.6 km/h).
If you’re wondering how much power the eight-cylinder engine makes, a dyno test from last year showed a colossal 514 hp and 675 Nm (498 lb-ft) of torque. That’s quite a standout against the ND1 or ND2 Miata, which hit just 181 hp and 151 lb-ft (205 Nm) for the facelifted version that launched with the 2019MY.
Incorporating a large V8 engine certainly adds weight to the 2.0-liter four-cylinder engine as well as affects the distribution of the factory’s ideal 50:50 car, but it should still be a very light car by today’s standards. Even in the slightly heavier RF flavor, the Miata hardtop weighs about 1,100 kg (2,452 lbs for the US model) in stock form.
The first attempt to destroy the 300 km/h barrier did not go according to plan. While the pint-sized roadster zooms in to top speed, the top windshield trim flies at 178 mph (286 km/h). Let’s just say the little Mazda wasn’t designed to achieve these kinds of speeds. Since the analog speedometer only reaches 150 mph (240 km/h), a professional data logger (Racelogic VBOX Sport) must be used to accurately measure vehicle speed.
According to its owner, the chubby Miata could have gone faster because “the speed kept going uphill” but there wasn’t enough straight ahead in front of the famous German highway. Although it “only” reaches 187.4 mph (301.6 km/h), it’s probably the fastest road legal MX-5 in the world.
