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Discussion Starter #1
Have pulled my Autolite 3924 plug, original gapped to .045. They have approximately 5000 mi. My engine is a 333 running a Performer RPM intake on top of TW 170 heads and Tri-Y coated headers, 10.6 static CR, premium fuel etc. It's plain to see, the end plugs 5 & 8 are noticeably darker than 6 & 7, but then, the engine had idled for "minutes" while checking the timing, then, pulled into the garage to cool.
Plugs 1 thru 4 look are more consistently the same, all dark.
The gaps, vary from .044 to 048. Perhaps, I had too many adult beverages when I gapped them, LOL!
There is some "richness" going on, but then, I've been playing with the Weber carb idle and and main jets, recently. Am planning to connect my AFR reader and maybe data long the results. In the coming weeks am going to visit a local Chassis Dyno. Hopefully, will learn from the AFR graph.


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