The Mazda MX-5 has been widely hailed as a return to the original formula: a great-handling, lightweight car. It's also been criticized by some for only having 155 horsepower. Mazda has repeatedly stated that it will focus on making the car faster by cutting more weight, but a new VIN filing shows that the MX-5 might also get a significant horsepower bump for the 2019 model year.
A document filed with NHTSA on February 27th shows that the MX-5 will continue to offer the trim levels we're familiar with and a 2.0-liter engine, but the power rating has changed from 155 horsepower to 181. This would constitute a power increase of 17 percent—the biggest jump for any version of the naturally-aspirated SkyActiv-G motor.
The horsepower increase is shown on Page 3 of the document, embedded here:
Naturally, we're a bit skeptical that such a power increase is possible: currently, the most powerful version of the 2.0L SkyActiv-G produces 162 horsepower in some overseas versions of the Mazda3; the VIN document that references the assumed Miata power increase does not list any power adders such as a turbo or supercharger. Our first thought is that the MX-5 might be getting the SkyActiv-X engine which Mazda states will make in excess of 180 horsepower in 2.0-liter form, but Mazda has said in the past that the MX-5 would not get this innovative compression-ignition gasoline engine anytime soon.
This gap in deployment of the SkyActiv-X engine might actually explain the power bump. The MX-5 will be due for a refresh soon, and engineers might be working on squeezing out a bit more power if they plan to continue using the SkyActiv-G engine. Adding 26 horsepower to that engine will be no easy task: it will likely require changes to make the motor breathe easier while staying emissions compliant. The most common aftermarket upgrades to intake, exhaust, and computer only add about 12 horsepower to the current engine. There are a few tuning packages that , but they require extensive mods including new camshafts and intake manifolds.
Mazda has done similar upgrades to previous generations of engines, like the 2.0-liter MZR of the last-generation MX-5 which debuted at 136 horsepower in some models but was tuned to go as high as 167 horsepower in others. Mazda has stated it doesn't plan to offer a turbo version of the current car, as it would require significant weight-adding drivetrain alterations that would deviate from the current car's lightweight formula. This might be another reason for a breathed-on version of the current engine, as the jump to 181 horsepower would likely not require upgrades to the transmission, rear differential, or wheel bearings—the weight increase would be minimal.
We asked Mazda for comment on the document but their representative stated that they could not speculate on future products. While this is a common response for products that have not yet been revealed, it gives us some hope that the number in the document is not a mistake, since it was not immediately pointed out as such.
While most of us here at R&T believe that 155 horsepower is plenty for a car as light as the MX-5, we can all appreciate that this apparent power bump would make the Miata even more fun on the road and the track.