The colder plugs are for high speed operation. If your engine is running that badly, I doubt you will be doing any of that. The 14's won't hurt for normal driving, but I doubt they will solve your fouling problem. Do you know the cause of the fouling? Russ Vaughan goldenlion413@xxxxxxx wrote: Hello 300 club. Will it hurt the engine on my chrysler 300F if i use champion J-14 Y spark plugs because every other spark plug i use seems to foul out in about two days thanks for any help tom powers from catskill ny. [Non-text portions of this message have been removed] To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/ Yahoo! Groups Links [Non-text portions of this message have been removed] To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/