Skunk2 say that "when installing Skunk2 retainers, make sure that the clearance between the top of the retainer and the tip of the valve is between 0.025 and 0.060 inches".

I never checked this when i put my retainers and springs in. What happens if its out of this range?

This clearance is not adjustable and its down to the valve keepers and as Skunk2 states there are atleast 4 different sizes. Therefore does anyone know what heads come with what sizes? And what size valve keepers will stay within this range?