After the debut of the 2018 Audi RS3 at this year’s Paris auto show, we sat down with the man who has run the RS program for the past 18 years to learn more about the all-new, all-wheel-drive sport sedan with a turbocharged inline-five engine. Want to know what Audi Sport’s head of development, Stephan Reil, had to say?
1. Development started by deciding what to change on an S3 sedan to turn it into an RS3. Tires, powertrain, chassis, driver assistance systems, and all-wheel-drive tuning topped the list.
2. Existing knowledge from the development process for Europe’s RS3 Sportback was leveraged for the RS3 sedan. Main vehicle components, save the powertrain, are the same as the RS3 Sportback.
3. The turbocharged inline-five is completely new. “Only bore, stroke, and displacement are the same,” says Reil. “Everything is new.” Switching from the Sportback’s cast iron engine block to an aluminum block saved some 60 lb. “As you know, there’s no better place to save weight than the front of the wheels,” says Reil.
4. The aluminum engine had to stay roughly the same size as the cast-iron one. Had it been any longer, it would not fit in the engine bay transversely.
5. The aluminum engine needed a completely redesigned, stronger crank housing. “There was a lot of simulation and calculation to have the engine strength using aluminum,” says Reil, noting that characteristics of aluminum are completely different from cast iron. Even the cast-iron engine used a special cast iron, typically reserved for the TDI engines with a lot of combustion pressure.
6. Audi Sport developed the RS3’s engine in parallel with TT RS’ engine. Both the RS3 and TT RS have 400 hp and 354 lb-ft of torque, and both will go from 0 to 60 mph in just over four seconds.
7. “The [RS3’s] five-cylinder has the best sound in the world.” At least Reil thinks so, and we can’t wait to see for ourselves.
8. The exhaust went through about 30 iterations during development. The engine has an uneven firing order (1,2,4,5,3) with an angle of 144 degrees, so the exhaust waves going through the system are “wilier” than typical engines. A lot of thoughtful, careful sound design went into the RS3’s active exhaust system.
9. There were no major hiccups during development, and Audi Sport wouldn’t have done anything differently on the RS3. “It was a quite successful approach, and…yeah, everything on the wish list made it,” says Reil.
10. The RS3 underwent two 8,000-km (4,971-mi) durability tests at the Nürburgring Nordschleife. The first test happened with a protoype car, and the second test happened with a production car. Racing drivers were given laps times to meet and beat. One of those racing drivers was Frank Stippler. “There are a lot of guys who can drive a car at the limit, but there are few who can help you with development,” says Reil. “Because Frank has a complete engineering background and because he is one of the fastest guys on the Ring, this is very helpful to get his feedback.”
11. Not that Audi Sport does everything Stippler says to do. “Because then it would be a real race car,” says Reil. “It would not be suitable for the street anymore.”
12. So don’t think of the RS3 as a track-focused car. “The car is suitable for the track but if I were going to the track, I would use another car,” admits Reil. “I would use a TT RS.”
13. Audi considers the Mercedes-Benz CLA45 AMG as the RS3’s only competitor in America. When asked, Reil struggles to come up with another car that the RS3 will compete with. He mentions the BMW M2 but quickly dismisses it for using rear-wheel drive.