I dont know any Audi forums so I am posting this here. Ya know how the S4 and I think all the 1.8 turbo's have 5 valves per cylinder? Is it 3 valves for exhaust and 2 for intake, or the other way around? What is the advantage to having the extra valve??

 

the 3 valves are on the intake side, 2 on the exhaust side. you get better flow out of 3 smaller valves than 2 bigger ones. and because the vavles are smaller, and less mass must be moved, you can rev the engine to a higher RPM