Two more leading edge Audi FSI and TDI engines join the all new A5 coupé range this week with additional refinements that boost output while at the same time maximising efficiency. The 2.7-litre TDI and 3.2-litre FSI units power the A5 2.7 TDI priced from £31,640 OTR, and the A5 3.2 FSI at £33,230 OTR. Both will reach their first UK customers in late October.

The 3.2-litre V6 FSI petrol is a development of the much praised unit powering A4, A6 and A8 models, its power increased in the A5 from 256PS to 265PS and its 330Nm torque peak delivered lower down the range at 3,000rpm, and across a wider band stretching to 5,000rpm. The A5 3.2 FSI takes a minimum of 6.6 seconds to reach 62mph from rest, can reach an electronically limited maximum speed of 155mph and yet is also capable of returning up to 31.7mpg.

The new 2.7-litre TDI with advanced common rail piezo injection and standard diesel particulate filter (DPF) enjoys a power hike from 180PS in the A4 and A6 to 190PS, and a 20Nm torque boost to 400Nm at 1,400rpm. It enables the A5 2.7 TDI to accelerate to 62mph in 7.6 seconds, to carry on to a top speed of 144mph and to cover up to 42.2mpg.

Both new versions are initially available exclusively with unique-in-class multitronic continuously variable automatic transmission (CVT), and in conjunction with front-wheel-drive.

The most important new development to benefit the engines in their transition to the A5 can be found in the 3.2 FSI. In its latest application this advanced unit combines the many advantages of FSI direct petrol injection with a sophisticated new Audi valvelift system first seen in the new 2.8-litre FSI unit powering the A6 and the recently introduced A8 2.8 FSI – the luxury saloon with the lowest CO₂ emissions in the UK market.

Audi valvelift controls valve opening far more precisely than conventional systems, boosting fuel economy by a remarkable 10 per cent. Valve lift is variable between two levels through the use of sliding cam units mounted on the intake camshaft. When strong acceleration is required, an electronic control mechanism selects a cam profile which opens the valve as fully as possible for optimum ‘breathing’. When throttle usage is more relaxed, the control mechanism selects a lower profile, reducing the amount of fuel and air compressed.

In addition to the new engines the A5 range also includes an upgraded version of the 3.0-litre V6 TDI with 240PS and a 4.2-litre V8 FSI petrol engine with 354PS reserved for the flagship S5 quattro.