Is that the correct step up for the NGK copper plugs.(1 step colder) 50-75 dry shot? I looked through the NGK catalogue @ work, the the website, but it seems itd be a ZFR7F-11, yet Im not seeing anything. What do the prelude/nitrous guys use as far as plugs go?

 

Didn't you post this in the Prelude forum? See my response there.

 

yes, the more I poseted, the sooner it gets answered Thanks for your reply