4:10's and a torque converter since its an auto, but this would probably put you over a 1000 I dont know how much torque converters cost I dont shop for auto parts, I hear tranny coolers help the autos out too. Im pretty sure if you change the gears in the autos you need a chip to go with it to change your shift points or you can cause transmission damage, and chips that arent tuned to run premium you probably arent gonna notice a differance in performance If you want to go fast it would be cheaper to just trade up to a 99+ since the engines make 35 more hp with the PI heads like everyones saying.