Spark Plug Comparisons & Explanations

Since there was a recent post about spark plugs and I had some info I thought I'd list some sites here where people can get comparisons and explanations of what features are important. I hope somebody finds the info useful.

http://www.centuryperformance.com/spark.htm

http://www.cts.com/browse/nology/silverdetail.html

http://www.halosparkplug.com/products.htm

http://www.knite.com/ignition_challenge.htm

http://www.edelbrock.com/automotive/sparkplugs.html

P.S. Here are more sites I found:

http://www.centuryperformance.com/spark.htm

http://extension.usu.edu/publica/agpubs/fm/fm26.pdf

http://www.zccw.org/Tech/Ignition/PlugBasics.html

http://www.torontokartclub.com/tt_plugs.html

http://www.babcox.com/editorial/cm/cm120032.htm

http://www.iridiumpower.com/faq.asp