valve float

Hello racers,
I need some opinions,,,I believe i am getting valve float at about 5800 rpm.
I have edelbrock performer rpm heads,,comp cam xe-268 h cam,,1.6-1 crane rockers.
If i changed back to 1.5-1 stock rockers would that get rid of the valve float?
should i add shims to the springs or get new springs?
if i change back to stock rockers am i going to notice performance loss because of the lower valve lift?
any and all advice is appreciated.
Clark