Much of the automotive industry has already begun to turn away from putting diesel engines in passenger cars. We can still expect to see them in something like a pickup or ladder-frame SUV. Lately, however, diesel and performance have been rather mutually exclusive, but Audi wants to shatter that notion by sticking in a hot diesel in their S4 sports sedan.
Audi insists that this particular S4 isn't just an A4 TDI with sporting bits attached to it. The new S4 TDI uses the familiar 3.0-liter V6 TDI engine used in just about every midsized to large car within the Volkswagen Group. But what Audi has done is uprate its internals and its turbo. The result is 347 PS and a whopping 700 Nm of torque. While it's still slightly down in terms of horsepower compared to its gas-fed counterpart (354 PS), it's up by a massive 200 Nm against the standard S4.
With figures like that, Audi says the diesel S4 matches that of other high-performance sedans. According to their own figures, the S4 TDI rockets to 100 km/h from a standstill in 4.8 seconds. Top speed meanwhile is electronically limited to 250 km/h. Because it is a diesel, it is said that it can also return reasonable fuel economy.
Audi rates the combined fuel economy, which is a mix of city and highway driving, at 6.2 liters per 100 kilometers. That translates to 16.1 kilometers per liter. With a fuel tank capacity of 58 liters, the S4 TDI has an approximate range of 933 kilometers on a single filling.
This being an S4, Quattro all-wheel drive is standard, along with a sports differential that aids in handling. The lone transmission option is an eight-speed automatic. Also, the only noticeable exterior difference between the TDI and TFSI (gas) S4 is the foglight housing, which is U-shaped in the diesel.
While significant, this isn't the first high-performance Audi diesel. Just a few months ago, they unveiled the S6 and S7 TDI. The S4's bigger siblings use the same 3.0-liter diesel and put out the same numbers. Audi was also close to bringing the R8 TDI concept to life about a decade ago but, sadly, did not push through. The diesel R8, had it gone to production, would have used a 6.0-liter V12 mill with 500 PS and 1,000 Nm of torque.
But if you want your performance vehicle wrapped in an even more inconspicuous maner, Audi is also putting in the same engine in the Avant station wagon body style.
You may be wondering why Audi is making performance diesels in an era where almost everyone is pushing towards electrification. We won't know the answer to that but you have to remember that Audi was the first to enter a diesel in Le Mans and won. Perhaps then it's their way of saying that diesel still has something to give in this day and age.