Went to the track yesterday and found out my posi is shot. Looks like it's time for a 12 bolt. Do you guys know where the best place to get one? What posi should I get? I was also wondering if I should keep my 4:10s. I had to get off it twice because of wheel hop and still trapped at 111. I don't want to have to shift into 5th. Will the 12 bolt lower my mph or should I get 3.73s? I'm pretty much done modding the car. Only thing I will get is some sticky tires with the 12 bolt.