Spy shots have caught the car running around in what looks a lot more like Subaru guise than the Toyota FT-86 concept version revealed earlier this month, and talk of a special high-output model has been around almost as long as rumors of the new Subaru coupe have. But a new report cuts through the innuendo and claims an STI--Subaru Tecnica International, Subaru's in-house performance division--treatment that's good for 250 horsepower is already in the works.

According to the newest report, the up-rated car still won't be turbocharged, however, with a 2.5-liter boxer engine doing the work. The extra half liter over the expected standard 2.0-liter engine will translate into not very much more weight, so the extra 50 horsepower will be easily felt.

Adding the cost, weight and complexity of a turbocharger would likely push the price too high and require output closer to 300 horsepower in order to achieve the desired performance. On the other hand, turbocharged cars are more easily modified for greater performance, and adding to the stock Subaru configuration is a long-standing tradition with die-hard brand loyalists.

One possibility is that Subaru will introduce two up-rated models, much like the Impreza line features the WRX and STI. A 2.5-liter naturally-aspirated 250-horsepower car could slot between the base 2.0-liter car and a turbocharged version rated at up to 300 horsepower. In this scenario, the highest-performance model, much like the Impreza WRX STI would be targeted at a limited audience, and would command a premium price.

We don't expect to see the new Subaru version of the joint sports coupe until the 2011 Tokyo Motor Show, but it should appear in concept form before then. The Subaru version hasn't yet been officially approved for production, however, meaning that all of these plans might yet come to naught.

If the car is built, expect it to feature a standard six-speed manual transmission, rear-wheel drive and a starting price under $25,000 for the base 2.0-liter car.

[Auto Express]