A HIGH performance diesel version of the Audi Q7 SUV will be returning to the line up later this year with its engine backed up by a 48-volt electrical system.

The new Audi SQ7 TDI develops 435ps from a 4.0-litre biturbo V8 which is enough to give it a 0 to 60 acceleration time of 4.8 seconds. Top speed is restricted to 155mph.

The 48-volt electrical subsystem feeds an electrically powered compressor that assists the two turbochargers whenever the load demand from the accelerator is high while the energy in the exhaust gas is still low.

As a result, up to 900Nm of torque is available instantly at any time - when accelerating from low speeds and particularly when starting off.

The engine is mated to an eight-speed automatic gearbox and the SQ7 comes with Audi's quattro all-wheel-drive system.

In line with other Q models from Audi the latest SQ7 has a revised grille with its looks set off by matrix LED headlamps.

Inside, the SQ7 TDI features leather sports seats,, S embossing, rhombus stitching and pneumatic lumbar support adjustment.

In the range topping SQ7 TDI Vorsprung models the seats are also climate controlled and feature a massage function.

Fuel economy figures and pricing are still to be announced and Audi says the SQ7 will be on the road in the autumn.