BEST Spark plug - 383

440SCOUT said

i use the rj14yc (63) champions in my older big blocks but since yours sounds like its had a refresh i would say the 12s are good...
ive never used the acdelcos in any mopars but i know they work good in gms
i agree on the splitfire but i would like to elaborate... those are the worst plug ever imho...
doug

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RJ14YC are hotter than RJ12YC, right..?

My engine, which came form a '69 Road Runner, is supposed to run the RJ12YC..but I understand that with the quality of gasoline found today, it is recommended to run a "Hotter" plug.

I think that may be the RJ14YC...

Any ideas on equivalent part # for NGK's or AC Delco's..?