The 9l will be plenty in your pede. These motors have tons of power, and in a 2wd truck it will easily spin the tires or flip the truck over. I run a 9l in a tube frame 1/7 scale buggy that has a pede tranny and suspension and it has no trouble pushing that heavy beast over 45mph. The 8l and 7l will require lower gearing and will run hotter.