Budgetmoparman
Well-Known Member
I picked up new plugs for my 440 that I just rebuilt. The plugs I got are champion RJ12YC. The problem is that my heads have a small bump just below the spark plug hole. The motor is originally out of a 1976 motorhome. Is there a special smaller diameter plug that chrysler used? The threads are the same but the part of the plug just after the threads is too big. Hopefully someone will understand what I am talking about and point me in the right direction.