"better for the environment" is a laughable claim, but at WOT a turbocharged engine making X power will be slightly more efficient than a naturally aspirated engine making the same power due to the recovered energy from the exhaust. Only at WOT and only at the same power output, tho... Pretty much something you'd only experience in a laboratory.And I want to know how a turbocharged engine is "better for the environment"? All a turbo does is stuff more air into the cylinders, so you can burn more fuel and get more power.