Twin-turbo BMW V8 is three months away
BY MARTON PETTENDY | 9th Sep 2008
At about $25,500 higher than X6 35d twin-turbo diesel ($120,530) and more than $30,000 above that of the twin-turbo petrol X6 35i ($114,705), BMW says the X6 50i is aimed most directly at Land Rover's Range Rover Sport 4.2 V8 Supercharged ($144,880) and the Porsche Cayenne GTS ($153,500).
The most expensive X6 pricetag will be also positioned about midway between the Mercedes-Benz ML500 ($127,500) and the ML63 AMG ($167,500), as well as being $23,000 dearer than BMW’s own X5 4.8i ($121,908).
As the highest-performing non-M engine from BMW, the force-fed 4.4-litre direction-injection V8 falls short of both the naturally-aspirated, high-revving Vee engines that power the M3 (309kW/400Nm 4.0-litre V8) and M5 (373kW/520Nm 5.0-litre V10), at least in terms of peak power output.
Naturally, it also fails to match the grunt of the AMG-built 375kW/630Nm 6.2-litre V8 in the ML63, which has a 2310kg kerb weight and consumes an average of 16.5L/100km but sprints to 100km/h in a claimed five seconds dead, toppling the 368kW/700Nm twin-turbo 4.8-litre V8-powered Porsche Cayenne Turbo’s mark.
But with 300kW available at a lowly 5500rpm and 600Nm of torque from just 1750rpm, BMW’s new twin-turbo bent eight is enough to propel the 2190kg X6 50i to 100km/h in a still-sportscar-like 5.4 seconds.
The X6 50i does so while returning average fuel consumption of 12.5L/100km, along with average CO2 emissions of 299g/km – matching the 261kW/475Nm 4.8-litre X5 4.8i (which weighs 20kg less and sprints to 100km.h in 6.5 seconds) and using just 0.4L/100km more than the X6 35i (0-100 in 6.7 seconds).
BMW makes no mention of fuel efficiency but says the X6 50i “has more power and torque than its closest rivals and is significantly lighter as well, underlining its superior acceleration performance”, referring to the Porsche Cayenne GTS and flagship Range Rover Sport.
Featuring two low-inertia turbochargers that are packaged with its vee and spin to 175,000rpm, the same new top-shelf BMW engine will power the flagship 750i version of next year’s redesigned 7 Series limousine flagship, which should cost close to $250,000.
It should also eventually grace a new 550i sedan replacement for around $170,000, meaning the X6 50i will provide the lowest entry price for BMW’s new V12-shading TTV8.
The 50i is differentiated from lesser X6s via unique 20-inch alloy wheels, satin-finish window surrounds, titanium-coloured kidney grilles, a satin chrome side strip and two rectangular chromed exhaust outlets at either side.
Inside, premium “Nevada” leather trim is standard, with options including perforated hide with seat heating and ventilation, and four interior trim finishes: ash or bamboo dark grain fine-wood, aluminium or “aluminium flywheel black”.
Exclusive 385mm brake discs with floating aluminium callipers are also fitted front and rear, while the range-topping xDrive50i comes standard with otherwise optional equipment including self-levelling pneumatic suspension, power-adjustable front “comfort” seats, four-zone automatic climate-control and a 16-speaker audio system.
Other options include aluminium side steps, roof-rails, an automatic tailgate, sunroof, soft-close doors, active steering and, yes, metallic paint.
The X6 50i employs the same new front-rear torque distribution system from which the X6 variants take their “xDrive” names, plus their Dynamic Performance Control technology, which BMW debuted on the X6 and is able to direct drive forces between both rear wheels.