which would cfl would help them the most

ok so i have 3 6500k cfls in my grow at the moment i dont need more light i will add more if i do need it though
my question is should i replace one 6500 and add a 2700k they already been on 12/12 for 5 days and they have no flowers yet
will they flower with out 2700?
what are 2700 useful for?

change as soon as possible they wont flower under anything over 3000k