Audi's dependence on diesel sales makes it especially keen to take back the high ground in diesel development. It was led by its rivals to the adoption of refinements like common-rail fuel injection and “intelligent” piezo injector technology.
More recently, the company has announced its intention to bring to production electrically-driven turbochargers (already used in its racing programmes), as a way of cutting turbo lag, in a new range of performance-oriented diesels.
Referring to recent progress with diesel research, Stadler reckons his company "is now the strongest" of the premium marques, noting that on average TDI engines have doubled in power in 25 years, while their output of toxic emissions has declined 90 percent.
Furthermore, Audi engineers believe efficiency advances of another 15 percent are possible before the end of the decade.
Stadler believes diesels could dominate Audi's range as far ahead as 2030, though he believes plug-in hybrids will play an increasingly important role. "Electrification is much more expensive than continuing to improve the combustion engine, so we believe the TDI will continue to have the biggest impact for quite a long time."
On performance diesels, Stadler acknowledges that Audi is working to ensure its diesels “deliver an RS feeling” as well as the expected high torque and good fuel economy.
He is coy about confirming the strong rumours of a diesel-powered R8 supercar, but points out that Audi is the one premium manufacturer that has continued to offer V8 diesel engines. "Why shouldn't we have high performance diesels,” he says, “if that’s what the customer wants?”
Despite reports that Audi is concerned about strong Californian sales of the battery electric Tesla Model S — currently running ahead of Audi’s own sales volume in that area — Stadler insists Audi will stick with plug-in hybrids as its preferred electrification route, rather than chasing Tesla (“a new kid on the block”) into pure electric cars.
“We are thinking of the customer and their needs,” he insists. “They wants to be able to drive where they wants, without worrying about battery range, or whether new infrastructure is in place. In a plug-in, they can do that. In an efficient way.”
Stadler is especially bullish about UK sales progress, describing the local market as “a lighthouse in Western European sales”. Audi volume has doubled here in the past five years, reaching 142,000 units in 2013, well ahead of BMW and Mercedes, with another record in prospect for 2014.
Sales for the first half of this year amounted to 83,761 units, a further rise of 13.5 percent.
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