Sancho805

one tune loaded into car at a time. if you start with an 87 tune and decide to load in a 93 tune, then you NEED to get your tank near empty and fill with the specific octane before loading the tune. if you go from 93 back down to 87, no need to empty tank first. However, you car should still run best with the correct octane for the specific tune. 87tune/87octane, etc.

my first mustang

Get a cai and a good axleback muffler too(or a GT takeoff). These 3 mods work great on the V6 Mustangs.

black08mustang

thanks for all of this information