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Correct spark plug gap

CaboJohn

Regular Contributor
I have 2003 Captains Choice MPI 350s. Manual says the correct gap is .060. Recently I ran across several posts on Hull Truth where owners were saying the correct gap is .035 or in some cases they said .040 or .045. The argument made was that the engine has known problems with cross firing due to poor design and materials in the distributor cap and rotor. If you reduce the gap, the overall resistance in the system is lower and you have less problems. They also note that the .060 was specified in automotive designs to reduce pollution in lean idle situations but that it really had no benefit in marine engines, and in fact was not as effective under load as a smaller gap.

Any thoughts on the subject? Has anyone tried (or heard of trying) smaller (traditional sized) gaps and have you found any benefit?
 
I would say the gap size won't change the effective resistance much...and the factory (modern) spark generators usually have more than enough energy to give you a clean spark...If you are using a 'standard' plug, i would think 0.045" is plenty...
 
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