In this sense 'a turbo' is a car — a car with a turbocharged engine. Car people talk this way: 'He drives a turbo', 'It's the turbo, not the standard model'. It is casual, spoken, a bit enthusiast-ish; you would see it in a car magazine or hear it from someone who loves cars, and it often appears on the back of the car itself as a badge. Confusingly, 'turbo' is also used by the same people for the turbocharger part itself — 'the turbo went bad', 'you can hear the turbo spooling up' — so which one is meant depends on the sentence. And it lives a third life as a word meaning 'extra powerful, extra fast', stuck onto other words half-jokingly: turbo mode, turbo button, turbo speed. That last use has spread far beyond cars, into games and software and everyday exaggeration, though actually it usually just means 'the fast setting' and has nothing to do with any real turbine.