Encounter - The Audi Technology Magazine 2/2013
The 4.0 TFSI is a fascinating and powerful sports engine – it takes Audi’s downsizing strategy into the full-size class. The high-revving V8 biturbo with its aluminum cylinder block is systematically laid out for low charge cycle and flow losses, and develops its torque of up to 700 Nm quickly and from low down the rev range. Adjustable flaps in the intake channels set the incoming air into a cylindrical rotation, and optimize fill and combustion in accordance with their setting. The exhaust side of the cylinder heads is on the inside of the V, with intake on the outside. The two twin-scroll turbochargers (not shown here) are located with the intercooler inside the V between the cylinder banks – a layout that ensures short gas paths and dynamic response characteristics. The cylinder on demand system makes a major contribution to the high efficiency of the 4.0 TFSI.