How can turboing a Hummer give you better gas mileage and more HP?

My old soccer coach has a Hummer. He was telling me how he was going to put a turbo on it. He said by doing this he would get more HP and better gas mileage. I asked him to explain how that is possible. He told me by slamming more air into the pistons the fuel burns cleaner and explodes better. So it increases efficiency with a boost of power. Is this possible?|||What he says it true ONLY IF the turbo boost is very low. It just overcomes the air resistance in any intake. It is like using ultra low restriction intakes. But we are talking about 2 or 3 psi.





but when the boost is raised, the engine works like bigger engine and uses MORE gas.


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My Audi A4 comes with factory Turbo (1.8L). So at cruise the turbo acts to increase MPG (it gets 33 MPG on the hwy). But while heavy acceleration, it increases HP. But on most turbo, it uses more gas in general (Audi is just very good at tuning).








Good Luck....|||dont bother i have a hummer best thing thats way cheaper than 2 or 3psi turbo is cold air intake it will give it more air more hp and better mpg, with turbo ur forcing air into it...