what happens if you have 4:56 gears, 35" tires and computer not programed for the set up? are my miles guna rack up faster or anything other than my parking brake light, abs light turn on after 2 minutes of driving and my speedometer off... is it bad? should i get a tuner? or its not a big deal? thannks in advance

Just get a tuner, it'll be way easier.

Used predators and quadzilla's are pretty darn cheap in the classifieds.