Welcome to AF 2quik4u !
first on the traction control, when its off the car will usually spin the wheel pretty good, especailly if you were to put on a turbo.
As far as Mpg, I hav an SE mod'ed to the gills and get 22-24mpg in city driving. I also hav a GT stock, it gets the same city. THe both get 30-35mpg highway, and you can expect a little more with the 89octane fuel.
Now if you hav on the AC you loose quite a bit of umff and your Mpg will drop, mine does alot !
Heres a link for some parts and mods for your Grand Am.
http://www.automotiveforums.com/vbul...d.php?t=502706
Thiers only one chip I know of that you could buy, its the DHP from Parts For your Car. They were on sale for 99$(plus core).
To get the most out of the DHP you need a Cold Air intake, and a less restrictive exhaust, SLP or Borla make some good stuff.
Should be a turbo kit or super charger kit listed on the link from above. they run around and up to $4500
IF you hav any other questions, just ask, we'll be glad to help.