I have a zz4 crate engine and will be putting afr 200cc heads on and was thinking of the voodoo #60122 cam with .535/.550 lift and 231/239*.Just wanting to know if I can use the stock roller lifters in the engine or if I need to upgrade as the cams rpm range is 2400-6400 rpm.The lifters in the engine now sound like a solid cam,even after adjusting them several times,is this normal?