https://www.amceaglesnest.com/guide/index.php?action=history&feed=atom&title=Spark_Plug_Guide 2026-06-19T09:14:26Z Revision history for this page on the wiki MediaWiki 1.24.0 https://www.amceaglesnest.com/guide/index.php?title=Spark_Plug_Guide&diff=6781&oldid=prev 2011-07-24T12:06:42Z

<p>New page: Research by amceaglenest member &quot;Jurjen&quot; The Eagle runs best on simple plugs. Only disadvantage is that they wear out quickly (6000 mls) in combination with the high voltage ignition. I d...</p> <p><b>New page</b></p><div>Research by amceaglenest member &quot;Jurjen&quot;<br /> <br /> The Eagle runs best on simple plugs.<br /> Only disadvantage is that they wear out quickly (6000 mls) in combination with the high voltage ignition.<br /> I don't like plugs with multiple ground electrodes, because they cannot be adjusted.<br /> And last but not least, I like the ones that protrude into the combustion chamber better because I expect the flame front to be more even (less knocking and better MPG).<br /> Engines that are burning oil, are better off with plugs that have less protrusion<br /> See and read under tip protrusion:<br /> <br /> http://en.wikipedia.org/wiki/Spark_plug<br /> <br /> Here we go:<br /> <br /> Truckplugs Champion 4412<br /> Some off roaders like the truckplugs best, but they are not being made any more.<br /> <br /> Normal plugs<br /> Champion RC12ECC<br /> Autolite 985<br /> NGK ZFR5N<br /> Denso QJ16HR-Q<br /> Bosch FR9HC+<br /> <br /> Premium plugs<br /> Champion RC12PEC5<br /> Autolite AP 985<br /> Bosch FR9HP+<br /> <br /> Don't use (or only in engines that burn oil, to prevent fouling up)<br /> Champion RFN14LY (this is the plug advised by AMC)<br /> NGK ZFR4-11<br /> NGK ZFR5-11<br /> NGK FR5-1<br /> <br /> General data<br /> Thread 14mm<br /> Reach 3/4&quot; (19mm)<br /> Hex 5/8&quot; (16mm)<br /> extended projected tip</div>

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