Audi releases new bi-turbo TDI engine for A6 and A7 Sportback


Timing can be a bitch. That’s the first thought that came to mind when reading Audi’s press release for their most potent V6 TDI engine. At first glance 309 bhp and 650 Nm (480 lb-ft) of torque sounds unbeatable, unless of course you’re BMW.

Less than a week ago BMW revealed the 5 Series M550d. Same 3-litre engine capacity. Three turbos rather than two. 376 bhp and a truly class leading 740 Nm (546 lb-ft) or torque.

A quick check of their respective economy and emission figures; Audi – 44.1 mpg, 169g/km CO2 and BMW – 44.8 mpg, 165 g/km CO2 rubs further salt into the Ingolstadt car maker’s wounds.

If there’s a ‘rosy tint’ to this scenario then it might just be pricing of Audi’s new models. BMW have yet to publish those for the M550d Saloon and Estate, whereas Audi have confirmed the starting price of £43,810 for the A6 Saloon 3.0 BiTDI quattro climbing up to £53,435 for the A7 3.0 BiTDI quattro.

If you’ve watched the intro videos for BMW’s new M Performance diesels then you’ll remember they mention how good these new Tri-turbo diesels sound. Well, so do Audi. In fact Audi are so confident this is their sweetest-sounding V6 diesel, they’ve recorded a sound clip and posted it on Sound Cloud. Using an exhaust-mounted sound actuator, Audi’s engineers have been able to ‘tune’ the new engine to deliver a distinctly sporting soundtrack.

It all sounds mighty impressive, if not for BMW’s much more powerful, faster and more economical M550d.

Slotting in above the single-turbo 201 bhp and 242 bhp versions of the 3.0 TDI that already feature in the A6 and A7 Sportback ranges, the latest V6 engine has a two-stage turbocharger that delivers maximum boost of up to 3.2 bar, helping the A6 3.0 BiTDI quattro Saloon reach 62mph in 5.1 seconds, and the A6 Avant and A7 Sportback to do the same in just 5.3 seconds. Top speed for all versions is the standard 155mph (limited).

I hate to rain on Audi’s parade, but heck, we’ve already referenced BMW’s M550d by comparison – whilst 5.1 and 5.3 seconds is Audi’s quickest diesel performance, BMW raises that bar to 4.7 seconds for the M550d Saloon and 4.9 seconds for the M550d Touring.

Audi’s new BiTDI models come fitted with an eight-speed tiptronic transmission and the latest generation quattro all-wheel-drive system, which features a self-locking centre differential and torque vectoring for optimum traction and stability. But then BMW offers essentially the same configuration in its M550d.

Audi offers an optional sport differential, which distributes power in continuously variable proportions between the rear wheels to sharpen and quicken responses even further.

It all sounds mighty impressive, if not for BMW’s much more powerful, faster and more economical M550d.

As I said, sometimes timing can be a bitch.