Diesels are very popular these days. They perform well, with stump-pulling torque, and are vastly more efficient than their gasoline-powered counterparts. Whereas a few decades ago a diesel engine would be written off as a smokey, slow oil-burners, these days the demand is very high, and former negative diesel traits have all been eliminated due to the advanced technology->ke1701 of today.

Perhaps the most impressive diesel offerings come from the German manufacturers. BMW->ke178, Audi->ke14, and Mercedes->ke187 all offer several diesel engines that are every bit as desirable -- if not more -- as their respective gasoline versions.

Audi has an innovative new spin on the turbo-diesel with its A6->ke934. It is still a mono-turbo setup, but with an electric turbo chiming in to help out at lower revs. This innovative design will virtually eliminate turbo lag and provide even more oomph off the line than diesels are already famous for.

How does it work?

Click past the jump to read more about the 2014 Audi A6 TDI Concept.

2014 Audi A6 TDI Concept

Specifications
  • Make: Array
  • Model: 2014 Audi A6 TDI Concept
  • Engine/Motor: V6
  • [do not use] Vehicle Model: Array

Audi A6 TDI Concept in detail

The new, innovative mono-turbo design combines a regular, exhaust-gas-driven conventional turbocharger with a small electric compressor to aid in producing off-idle, low-end torque. Because exhaust gas is at a lower temperature in a diesel application, less energy is available to drive a turbocharger at low engine speeds. This is the reason diesels suffer turbo lag. While diesel torque is plentiful, there is usually a noticeable -- albeit short -- interval before the power kicks in. Audi's goal is to eliminate this.

The small, electric turbo is nestled between the regular turbocharger and the air intake system, and normally remains idle. However, when the car's ECU detects low exhaust gas energy at low engine speeds, the electric compressor kicks in immediately. While diesels are low-revers, with torque peaks beginning usually around 1,500 rpm, the electric turbocharger will provide instant response below this range.

Capable of 7 kW, the electric motor will accelerate the conventional turbo's compressor wheel to maximum speed in a lightning-quick 250 milliseconds, virtually eliminating turbo lag from idle. Audi is very adamant about the way these two turbos work together in harmony, and we have no reason to doubt its engineers.

Response isn't the only benefit of this new design; Audi asserts that this new turbo system will deliver improved fuel economy as well. Because this system will provide instant response, there is less downshifting, thus reducing engine speed and improving efficiency. Audi claims a huge increase in top-gear acceleration as well.

We can't wait to drive one. The U.S.-spec 3.0-liter Audi A6 TDI produces a hefty 240 horsepower between 3,500 and 3,750 rpm and a crazy 428 pound-feet of torque between 1,400 and 5,200 rpm; expect torque to kick in around 1,150-rpm mark, and expect to see a slight upswing in both torque and horsepower. The modified numbers are sheer speculation for now, as Audi only revealed the specifications on the RS5 with this technology.

What do you think about this exciting new technology? Let us know in the comments section!