Will these plugs work- I tried to get the retards at discount to help me, but they are as retarded as me

We looked up a colder plug and when I was reading Mikes garage about my nx1600- I remember him writing that the higher the number for the ngks-- the colder it is. Is this correct- will this plug (bcpr7es) work properly or does anyone have any suggestions? The guy there had suggested going with bcpr5e-11s but I swear I read that it was the higher the number the colder the plug with ngk's. Im pretty sure 5s are hotter though- thats how I detonated my motor in my nx with nitrous
