German tuner "Wimmer Rennsporttechnik" has managed to output 408 hp from the 2.0 litre TFSI engine of Audi S3. Several modifications of engine electronics, turbocharger, injection and other engine parts have been made to achieve that vast increase.

Before mods engine is producing 265 hp and 350 Nm and after, maximum torque increases to 540 Nm. The cost of the upgreade is 24,500 EUR.

Source:http://www.auto-motor-und-sport.de/d/134470

Official site: http://www.wimmer-rennsporttechnik.de/

PS. No official image is available. The photo is a regular S3.