APS, the UK importer of the Swiss tuning brand Sportec, has turned to North American-based VW specialist, STaSIS Engineering, for its newest project concerning the latest generation of the Audi S4. The STaSIS Signature S4 is available in two flavors, the Touring and the Challenge editions, with both featuring an engine kit that boosts the 3.0-liter supercharged V6's output from 333 bhp and 344