Cleveland spark plug recommendations
What is the best type of spark plug to help reduce pinging in Clevelands? I have 302 closed chamber heads (with the chambers relieved) on a 351. The plugs are not fouling but there may be some carbon build up in the chambers. I only run 98PULP (Ultimate) and my initial advance is set at 12degrees. I have tried everything but am reluctant to take off the vacuum advance. Any suggestions as to which plugs might help?
1978 XC Fairmont GXL, Emerald green, Jade Int. 351C, 750 VAC, C10, 9" LSD
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