I installed my bone stock charger & injectors,untouched 15/20R 4 blade went to a 82mm nozzle and a short shuttle ski went 77.3mph @8040 with gauge showing about 7.25psi boost.. I need about a 84mm nozzle and stock nose cone may go a bit higher but I'm just messing around. Actually I should have just taken out the ring all together ran it like that. I'm proud of my lil RXp bone stock motor and SC running that! Boy that B kit REALLY wakes up a ski the accelleration loss was unreal. I remember last yr at this time she went 77.0 @8400 with a 1st edition Riva sc impeller 15/20 with 1mm out 83mm nozzle but no skegs or 4 " air intake, or nose cone removed....