Originally Posted by Atariboy
Hit the button that would be A on a SuperNes gamepad (Never memorized the letters and colors on a 360 gamepad).
There's only 4 buttons though so I'm not sure why you had to ask. And there are menus you can bring up to show you what buttons the various functions are mapped to.
i looked at the buttons in game and seeing A,B and C don't help much, lol, done it now anyways was LB
Also this is the first time i ever played this game so i also didn't know i had to going top speed before holding LB for turbo