The twin-turbocharged 5.0-liter V10 engine of the RS6 Sedan delivers 580 HP between 6,250 and 6,700 rpm and a peak torque of 650 Nm (479.42 lb-ft) available from 1,500 to 6,250 rpm. It’s also capable of 0 to 100 km/h (62mph) in 4.5 secs and an electronically-limited top speed of 250 km/h or 155mph, which can be optionally raised to 280 km/h or 174mph. More.