I prefer to go to taller tires if possible to help these situations. also my hughs 3500 convertor seems awful loose, haven`t got to do any driving much w/ it yet tho. guessing from passed experience it`ll flash at least 4000-4200. have 28" rear drag radials on tit now, will go to a 29" eventually.-------505" 68 barracuda, 3;73 dana , 727 auto. ported alum. heads, fst 2.0 fuel I. ,