A POWER hike is on the way at Audi taking the high performance RS 6 Avant and RS 7 Sportback models into supercar territory.

The output from the 4.0-litre V8 biturbo engine which is fitted to both is being increased to 605ps which takes 0 to 60 acceleration down to just 3.7 seconds.

And with an overboost facility torque levels have increased to a maximum of 750Nm, adding to the venom.

The super boosted RS 6 Avant will cost from £86,000 and the RS 7 is priced from £91,600 - an increase of some £7,000 over the regular RS versions.

The ultra high performance cars will be arriving in February with order books opening in November.

With the added power - a rise of 45ps - the 0 to 60 time has been cut by 0.2 of a second and the full might of the revised engine can be unleashed with an optional ‘dynamic package' taking the top speed up from a restricted 155mph to 174mph for the Avant and 189mph for the Sportback.

Both are fitted with quattro all-wheel-drive with a revised differential to improve grip and in dynamic set up the adaptive air suspension lowers the body by almost an inch.

Cylinder on demand technology - which cuts out four of the eight cylinders on light throttle settings - is being used to enhance economy from the eight-speed automatic powertrain and that results in an official fuel return of 29.4mpg for the RS 6 and 29.7 for the RS 7. Emissions are 223 and 221g/km respectively.

The cars sit on 21-inch alloys and to differentiate from the normal RS models both have larger bumpers and front air intakes and a restyled rear diffuser.

Inside, sports seats with larger side bolsters and integrated head restraints are standard and so is quilted leather upholstery with coloured stitching and trim which includes a distinctive carbon inlay at the side of the centre console.