hey i need help on which plugs to use...i have the following in my car:

gsr block
type r pistons
b16 head w/skunk2 valve train
skunk2 stage 2 cams
chipped p28

i recently checked the plugs today to see that the tips were a grayish/white color but the base/threads were black...from reading other posts i'm getting the impression that my plugs are too hot for my application....right now i'm running ZFR5F-11 plugs....any ideas on wut plugs i should be running?

 

Yeah I would definitely step down to a 6 or a 7.