Both are the same except: The 6 and 7 numbers designate heat ratings. The 7 is a colder heat range than the 6. The colder range is better for forced induction. It helps prevent detonation.
The ZFR designates an extended plug, which is good for forced induction. It gets the spark farther into the combustion chamber for better flame front. The -11 designates that it is pre gapped at 1.1mm. Not sure what the F designates....anyone? I would stick with the ZRF7F as heat range is the most important for forced induction. Both are extended plug which is good. Steve ----- Original Message ----- From: <[EMAIL PROTECTED]> To: <[email protected]> Sent: Thursday, March 20, 2008 12:17 AM Subject: NGK spark plugs for turbo 99 > > What's the proper part # for the NGK plugs for turbo use? The ones I > had in my car before are ZFR7F-11, but I checked the the new ones that > I was about to put in and they are ZFR6F. > > --Ian > _______________________________________________ > Miatapower mailing list > [email protected] > http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower _______________________________________________ Miatapower mailing list [email protected] http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower
