[HWYSTR455]

What carb?

Any idea what your SCR is?

What head gaskets did you use when you replaced them, 1016s?

What intake gaskets?

What rear gears?

Steve25 & chiphead are pretty on target with line of thinking, colder plugs, 32 degrees TOTAL timing, rocker adjustment/setup, vacuum leak.

If your SCR is up there, a 2802 might be a better choice.

I was just commenting on another thread about NGK XR plugs, and NGKs in general, the temp jumps are in like 1.5 step each time, so they don't cross like one would think. I literally ran into this myself, and realized I was running a hotter plug than I thought.

There's also folks complaining many plugs these days are knock-offs, counterfeit, and may not be getting what you think.

Pics always help, post some.


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