Back in August, Ford revealed to us that when the doors open to the 64th IAA International Motor Show on September 13, it will be ready to exhibit four world premieres.

Since then, the Detroit-based automaker has told us about the EVOS sport concept and final production version of the performance Focus ST with 250-ponies, so if you do the simple math, there are two more cars left.

We’re still working on the last one but we learned that the third world premiere will be the performance Fiesta ST, thinly disguised as a concept study.

Chances are, the Fiesta ST will follow the path of the Focus ST that was first shown as a concept model before Ford confirmed its production.

Until recently, we weren’t sure if the sporty Fiesta ST would be equipped with a 1.6-liter or a larger 2.0-liter EcoBoost engine, but we now know that it will be the smaller displacement unit delivering somewhere around 180-horsepower.

More to come so stay tuned on Carscoop for our detailed coverage of the 2011 Frankfurt Motor Show premieres.

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