Few would call the 560-hp Audi RS7 underpowered. Yet Audi still felt it necessary to breathe more grunt into the RS7?s twin-turbocharged 4.0-liter V-8 engine. Dubbed the Audi RS7 Performance, the 605-hp model was introduced last year. Its extra power comes courtesy of a new turbocharger design, more efficient intercooler heat exchangers, a reprogrammed engine computer, and revised camshafts that activate new exhaust valves. A maximum of 553 lb-ft of torque is available from 2500 rpm to 5500 rpm in a temporary overboost mode. Normally, the engine makes 516 lb-ft at 1750 rpm and rides a wave that peaks at 6000 rpm?500 rpm higher than the standard car?s peak and only 800 rpm short of redline. READ MORE ??
...