The Audi new TT-RS was unveiled earlier this year, then, the new Audi RS3 is expected to come off to the 2009 Frankfurt Motor Show next month.

The new RS3 would be part of Audi’s largely unhindered new model onslaught, which has weathered the economic storm of the past 12 months better than most, despite facing some delays.

On the other hand, there isn’t really much development for Audi to do but tune up the handling and aerodynamics of the hatch and shoehorn the same engine found in the TT-RS under its hood.

As the spy shots show, the car itself bears no serious exterior modifications yet, indicating all of the mechanical upgrades will fit within the current car’s shell.

The area where the current S3 has its foglights is blacked-out on the RS3 test mule, however, indicating there may be something behind the front fascia taking advantage of the modified airflow. At any rate, a redesigned, slightly more aggressive front-end for an RS3 version is almost a certainty if the car does come to market.

Output from the turbo five-banger would likely be the same 340 horsepower and 332 pound-feet found in the TT-RS, which should be enough to propel a RS3 hatch from 0-60 mph in about five seconds.

However, there’s a chance that Audi may water down the potency of the engine in the RS3 so it doesn’t step on the toes of the TT-RS, despite the very different body types and target markets.

Even with ‘just’ 300 horsepower and Audi’s quattro all-wheel drive, the RS3 would be a daunting rival for the likes of the Subaru WRX STI, Mitsubishi Evolution X and Mazdaspeed3, especially considering Audi’s premium positioning.

With the premium hot hatch segment remaining fairly sparse these days, an RS3 model from Audi would also give the company bragging rights against rivals like the BMW 135i.

Production of the RS3 still isn’t completely certain, however, with company officials keeping mum on the subject. Today’s report from Sweden’s Auto Motor & Sport, however, indicates that the RS3 is indeed on its way.

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