Stock 5.7 Hemi with 545rfe trans. 373 gears and can not go faster than 130mph now. What do I need to do to get up to 145mph. Plan on doing an open road race in West Texas at Big Bend National park. It is 118 miles round trip and want to run the limit for my cars specs. What to do? FYI I do have Alterkation front and Firm Feel Leafs w Bilsteins. Handles very good now. Will add spoiler to front. I did not check my rpms when I was at top speed. I did have overdrive on. Do not know if that makes a difference. Looking for the simplest way of doing it.