Edman,
It is a well known fact that OE wires are carbon powder mixed with fibreglass. Not very condusive to the conduction of electrical energy. The high ressistance does eliminate RF interference, but the resistance does limit the flow of electric.
Plugs on the other hand are very critical to the combustion of an engine. There are heat ranges, plug depth, and seating differences to contend with.
For example.
My cousin has a 2001 Lincoln LS. It has 30,000 miles on it. He never drives it and when he doesnt drive it, he will start the engine for 5 minutes once a week. (I told him he is doing more damage to it by not driving it then he woud driving it, but that is a different story) Anyway, he was having a miss. I pulled the engine codes and it told me the number 4 cylinder has a misfire. I pulled that plug and it was bad. I stoped by the parts store to buy a plug. NGK did not match the plug. The Motorcraft plug is made by NGK. Autolite, wrong thread length. OK. How about the Iridiums? The OE plugs are gasket seat, but the Iridiums were taper seat. We spent 2 hours trying to get plugs.
Do I really want to screw around with aftermarket plugs?
Tom