Great article here about the Audi 2.5 TSFI engine, known eg. from the Audi TT RS.
So maybe the five-cylinder is headed for extinction like the dinosaurs. But even the dinosaurs had a T-Rex, and the engine that’s at the top of the five-cylinder food chain has to be this: the snarling, turbocharged Audi 2.5 TFSI, which sees duty in both the Audi TT RS and RS3. With 360 horsepower and 343 lb-ft of torque in the U.S. TT RS, it is a truly fitting salute to Audi’s rallying engines of yore, which were also 2.5-liter five-cylinders.
You may know that VAG makes a 2.5-liter five cylinder for the Jetta and base Golf. That engine is widely considered to be a noisy, underpowered, inefficient dud, and is set to be dropped (see what I’m talking about?) in favor of a smaller turbo four. But thanks to some heavy re-working by the mad scientists at Quattro GmbH, this turd gets polished into a weapon of mass destruction.