So the other day I was talking to my friend and he told me his brother., who drives a stage 2 turbo jetta, can set his turbo on a mode that gives him 40 mpg and he can still drive pretty normally. its not as fast as when the boost is up. but what is that and can we do that with a turbo for our cars? my friend said it only works for VW and Audi

 

Wow that sounds very intersting. But honestly doesnt make much sense to me. Iam not getting how it works. If you put anykind of boost in a car, the ECU is gonna see that more air is coming it and pump in more fuel. So in theroy and turbo would give ou bad gas milage. Buts that my theroy it could be worng.

 

any fuel economy comes in pre boost, if the car gets 40mpg its not because of the turbo, its because you arent reving the engine high, and on top of that its the fuel maps that help define the fuel efficiency so in the end if it were adding less fuel during boost you would burn up the engine from running too lean

 

im not sure what it is maybe its like it shuts down the turbo or something restricting the engine? I dont really know id have to ask him myself my friend didnt give me enough information he doesnt know jack squat either

 

Turbos, if driven certain ways, can actually increase mileage and efficiency of your car. It has something to do with the fact that generally there is excess fuel wasted in exhaust that doesn't actually get burned. However, with a turbo, and the additional air it's forcing into the engine, it burns off all of the fuel and cuts down or eliminates that extra, unburned, fuel. So.. if a turbo is run on low boost and the engine isn't revved high and can actually make your car more fuel efficient.

There is a more detailed explaination by someone who actually has a good idea what they're talking about on howstuffworks.com

 

ah yes, low boost meaning 2 or 3 psi, which gives a better mixing of air and fuel that you dont get with n/a, but the thing is...... those cars arent running that low of boost

 

No, generally not.. but then again, lots of people do stupid ****... such as put a stage 2 turbo on their Jetta and then only run it at 2 or 3 psi...

Or, buy a Jetta in the first place and act surprised when it breaks and costs them a fortune...
And don't get me wrong, Jettas I've driven are fun and I love to drive, but also the people I know that own one have left me with no desire to ever own one.