I see on the JDM site that NGK TR6 plugs are for trucks with over #6 lbs of boost and two heat ranges cooler. While on the PSP site the NGK TR6 plugs are stated to be only one heat cooler and suggested for 4#. Instead PSP suggests the NGK BR7plug. Why the difference?? I will be at 16# should I trade in my TR6 plugs for these other ones?
