In 1999, Honda celebrated its 50th anniversary by building a roadster around an engine that had no business being in a street car. The S2000’s 2.0-liter F20C targeted 100 horsepower per liter with zero forced induction, and revved to 9,000 RPM in production trim — at launch, the most powerful naturally aspirated four-cylinder ever mass produced. Even the name was a tribute, nodding to the 1960s S500, S600 and S800 roadsters. BMW built the E92 M3 right as the entire industry pivoted to turbochargers, and deliberately went the other way. Its 4.0-liter S65 V8 traced its DNA to BMW’s DTM racing motor, with eight individual throttle bodies for an unforgettable throttle response, and a carbon fiber roof to keep the weight up high down. It was the last V8 M3 BMW would ever build.