VW’s ‘Dieselgate’ has seemingly put the final nail in the diesel car’s coffin, with four of the world’s biggest cities banning them from their centres within the next decade. It’s a shame really, especially when you remember Audi once stuffed a twin-turbo V12 fuelled by the oily stuff under the bonnet of a Q7. Arguably one of the most pointless car’s ever made by Audi, the six litre v12 diesel Q7 was a quarter of a million dollar middle finger to all those peasants in ‘normal’ SUVs.
While Audi’s new SQ7 would be faster thanks to less weight and a trick triple turbo (counting the electric, turbo-lag reducing compressor) V8 diesel, the V12 Q7 was about more than just speed. It was about big numbers and that engine. An engine Audi claimed to be closely related to its twice successful – and now cancelled, thanks again to Dieselgate – R10 Le Mans program.
Speaking of big numbers, the V12 Q7 weighed in at a monumental 2635 kilograms, but when you’re packing around twice as much torque as a V10 R8 weight is largely irrelevant. So irrelevant in fact that the big Q7 managed 100km/h from rest in five and half seconds and went on to an electronically limited 255km/h.
In order to achieve those frankly ridiculous performance figures, the big diesel churned out 500hp and a four figure torque output. Yup, 1000 of Newton’s finest metres delivered between 1,750 and 3,250rpm. These outputs were made possible thanks to 1.6bar of boost being jammed into the V12 by two, variable vane turbochargers. The variable vane turbos are commonplace in turbo diesel engines and change the angle of the exhaust gasses blown on to the impeller, aiding faster spool-up. Important when working within the Q7’s 4500rpm redline.
Interestingly, the V12 Q7’s Quattro four-wheel-drive system split torque 40:60 favouring the rear – a move Audi said gave “the vehicle a sporty, rear-focused driving style that guarantees maximum agility and driving enjoyment”. Yeah, right. Lets not forget that weight figure, which was 500 kilograms more than Porsche’s Cayenne Turbo, itself not exactly a light-weight. Unsurprisingly, there was no dual clutch gearbox transferring power to the wheels, just a traditional six speed torque converter automatic which, according to Audi, changed gears “rapidly and gently”. Good to know.
All V12 Q7’s were fitted with 20 or 21 inch wheels and while this pretty much sealed their fate to, well sealed roads, the huge wheels were needed to fit over the gigantic carbon ceramic brakes. The front wheels not only had to fit 420mm discs in them, but also eight piston calipers, while the rears ‘only’ had to contend with 370mm discs and four piston calipers. All of this was held up by air suspension, which Audi described as “highly dynamic”, what ever that means. The suspension did feature electronically controlled shock absorbers which allowed the big Audi to reduce body roll through a system it called dynamic roll stabilisation.
Now, hopefully I’m not coming across as being too critical of the big Q7 because frankly, I love it. Much of its appeal came from the fact that it didn’t shout about much better than you it was. Unless you knew to look for the huge carbon ceramic brakes and subtly different front and rear styling, you’d be none the wiser that the SUV in front of you was packing the most powerful diesel ever fitted to a passenger car. So while Dieselgate has killed the diesel, long live the V12 TDI Q7 – because there will quite literally never be a car quite like it again.