Just bought an 07 Chevy Aveo LS

[avguy]

Use regular gas - 91 is a complete waste of money in an Aveo. And I don't think you will find anything to significantly improve your MPG, assuming it is tuned and aligned correctly, and the tires and brakes are good. Is this highway, city, or mixed for the 27 MPG?

[anziil]

Mixed MPG. And if not much for mpg what are all the performance upgrades available for the Aveo. And a price range for each.