BMW has blessed its 6 Series coupe and convertible with a more powerful 4.8-litre V8 as part of a 2006 model year upgrade less than two years into the 5 Series-based model’s life.

On sale in Australia since May 2004, the E63 645Ci coupe and convertible will now be known as the 650i coupe and convertible.

First seen in the facelifted 750i flagship sedan released in June last year and made available in the 2006 5 Series sedan from January, the 650i twins offer the same increase in power and torque as the 550i and 750i do over the 545i and 745i respectively: 10 per cent more power and nine per cent more torque.

While the 645Ci delivered 245kW and 350Nm of torque from its 4.4-litre V8, the 650i’s new 4.8-litre version offer 25kW more peak power at 270kW (from 6300rpm) and 40Nm more peak torque at 390Nm (from 3400rpm).

BMW’s new V8 improves the 650i Coupe’s claimed 0-100km/h acceleration time to 5.5 seconds, while the convertible now takes 5.8 seconds – both in six-speed Steptronic auto guise.

Fuel consumption for the 650Ci is 11.1 litres per 100km on the combined cycle, while the convertible now uses 11.7L/100km on the same cycle.

Other new-for-2006 6 Series features include an updated iDrive controller with leather insert, an engine start/stop button, head-up display, latest-generation DSC+ stability control system and High Beam Assist.

The new DSC+ system includes Hill Start Assist, a Brake Standby function, Brake Drying function, Brake Fade Compensation and Comfort Stop features, while High Beam Assist automatically monitors traffic conditions and de/activates the high beam accordingly.

Remaining standard on both 650i models is Dynamic Drive, which controls anti-roll bar stiffness to reduce bodyroll by a claimed 80 per cent, as well as being linked to the steering, transmission and accelerator systems to make them respond more quickly when required.

Adaptive bi-Xenon headlights, active steering, a DVD-based navigation system and Professional sound system also remain standard.

At $204,000 for the manual and auto coupe and $220,700 for the manual and auto convertible, pricing returns to within $1000 of the 6 Series' original launch pricing, after dropping about $7000 for the 2005 model year.