ryan i had 4.30's in the mach1 and then traded them out for 4.56 then the blower made me shift into 5th in the 1/4 and dropped back down to 4.10.s do 4.30's you WILL NOT REGRET IT>>> by far my best na bolt on... i had done ported intake, intake spacer, cold air, exhaust catless hpipe and the gears had a better set of the pants feel than all the others put together.