never screwed, always run 15-18 lbs depending what the track will hold. my car went the fastest @ 18lbs. roll through water box and just whack the throttle to rotate the tires, stop and set line lock, place in second gear go to 5k, put in high gear and let off line lock, roll out about 4-5 ft and roll to the lights. been never any worse than 1.48 @ 4200lbs. no need for big burnout. tires will overheat as there soft to begin with