i was 280 brock pipe, +6, 16/43, all shorts and full box mod, welded hub/heavy springs, airshifter and my best motor mph was 113.43. even my bad launches were 111-112's. i switched to 16/45 and lost 20lbs and went to 114.33 on a motor with bad blowby that day. actually lost #4 cylinder later on a nitrous run.
you definitely need more gear