Once upon a time, Volkswagen built V-10 engines for its road cars. Throughout the 2000s the German company, formerly known for its popular diesel models, sold its full-size Touareg SUV with a twin-Turbo V-10 TDI. It was pulled from the US market in 2008 because it could no longer pass emissions tests, and has since become a mythical powertrain for the VW obsessed. A teardown reveals just how much effort engineers put into this engine to make it work.
