AUDI engineers have taken the already impressive 2.7-litre 30-valve twin-turbo V6 found in the S4 and turned it into something special with the RS4. Power increases from 195kW to 280kW between 6100 and 7000rpm, while peak torque of 440Nm (up from 400Nm) is available from 2500rpm to no less than 6000rpm. Redline arrives at 7000rpm. In conjunction with British Cosworth Technology, which has been part of the Audi Group since 1999, the cylinder-head has been redesigned and is produced using a specially developed casting technique. The admission and exhaust ports have been modified in line with the engine's higher performance, and the cross-section of the air ducts at both the intake and thrust side enlarged. The turbochargers have been enlarged and boost pressure has been increased compared with the S4. The use of larger charge-air coolers with less pressure loss has also improved efficiency. Quick? 0-100km/h is a claimed 4.9 seconds 0-200km/h requires 17.0 seconds and top speed is limited to 250km/h. EU fuel economy figures point to a thirsty 17.0 L/100km on the city cycle and 9.0 L/100km on the highway.