The technique behind the turbo is accually easy to understand. When you accelerate hard a turbine starts turning and pushes extra air into the engine witch gives you the opportunity to burn more fuel. This combination adds extra power to your car. This is accually amazing since it can add a lot of extra power even to smaller engines like a four cylinder one. You still have the fuel consumption of a small engine but in some cases you get the power of lets say a six cylinder engine. But if you want to save fuel I recommend to take it easy, fuel consumption skyrocket when you rev a turbo charged engine. Great for overtaking cars on the road but not so good for consumption. The technique works great though and the new once doesnt even have any lag. This was a problem back in the days but todays turbo chargers accuallt works great.