When Ford debuted the facelifted 2018 Mustang earlier this year, it failed to provide any photos of the entry-level EcoBoost model and now we know why, the car is still being developed.

Recently, three Ford Mustang prototypes were snapped in the midst of testing in Colorado and while only two have been adorned in the fresh skin of the 2018 model, all are alleged to have been installed with the 2.3-liter turbocharged four-cylinder. Compared to the GT V8, they’re missing the grille fangs and have two instead of four exhaust pipes.

Ford has yet to fully detail the EcoBoost-equipped 2018 Mustang but we already know that the 3.7-liter V6 has been removed from the range and the four-cylinder turbo outfitted with a 10-speed automatic transmission option.

The Blue Oval’s official word on the 2018 model is that it delivers more torque than the outgoing four-cylinder, meaning a touch over 320 lb-ft is on the cards. In terms of horsepower, there’s a strong possibility it will also get a slight nudge upwards over the current 310 hp figure.

From the prototypes spied, one of the 2018 models was a fastback and the other was a convertible. A pre-facelifted Mustang convertible was also being tested.

Ford says the 2018 Mustang will launch across North America this fall meaning we can expect further details about the pony car, including the EcoBoost variant, in the not too distant future.

Hat tip to Brett Borgard for the photos!

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