How do you know what my backgound is or applicable to this argument. How many "years and years" of design experience (mechanical-steel, electrical, precious alloys used in the electtodes , ceramics used in the insulator and heat transfer characteristicsg, engine, ignition, etc., as I have several professional engineering credentials) or are you are just characteristics, using the DFL factor? Car dealer Technicias/mechanics use the applicable brands......GM/AC, FORD/MOTORCRAFT, MERCEDES-BENZ/BOSCH, ETC......if the NGK brand is the "be- all to end brand" for all engine componenhhs, WHY ARE THEY NOT UNIVERSALLY INSTALLED IN ALL VEHICLE'S? You are certainly allowed to express your OPINION......But, do not assume you speak for me, as I have the same "right" to express my opinion and use whatever component i I deem necessary for my application
BOB RENTON