Check these links for reference
http://iwcweb.com/eclipse/html/warning.html
http://www.unofficialbmw.com/all/engine/all_dont_use_nology_wires.html
http://users.argolink.net/sutton/GSR.htm
Go down the page on the last one to:
Then when i took it for a test drive the car was misfiring pretty bad. Culprit: the Nology Plug wires were arching. This is probably what blew the ignition coil out in the first place. The coil was old and going to die soon, but the extra resistance from bad plug wires didn't help. Now I have custom plug wires made by Nathaniels.
Another quote:
"Nology
Nology claims in the ads that "2-5 % More Horsepower, More Torque, Higher Top Speed, Quicker Acceleration, Easy Starting, Better Running, Longer Life, No Fouling" will be available just by installing their plugs. They also go on to claim that "HotWires (TM) work on any engine and with any ignition system, and are custom-made to fit any application. (Legal for use only on racing vehicles which may never be used on a public highway.)" This is all done because "HotWires (TM) create the most powerful spark possible."
HotWires (TM) are the only spark plug wires with a built-in capacitor. This internal capacitor transforms any spark into a HotWire (TM) spark: a spark 300 times more powerful. HotWires (TM) produce horsepower. Aha, and if you believe this after reading this article, we must really talk about this bridge I know that is going for a rock bottom price. If you look at their ads we can see a) A side by side picture, one with a big, fat spark in the "Nology wire" side versus the ordinary side. Well, there is one glaring omissions in both of those pictures - we see a ground wire on one side, two pointy electrodes (a spark's best friend), and a blue high tension wire.. but no Nology wire! The pictures are true but they are showing you what would happen across a gap if you pump up the voltage 10-20X over the minimum needed to jump the gap - they are not showing actual performance of their wires under real conditions. B) A range chart of temperatures, etc., some of incredible levels. If we stop and think of these ranges for a moment we will quickly see that these kind of operating environments would immediately destroy a spark plug since it would arc out, melt into slag or simply evaporate the electrodes. What is a Nology wire finally? Just a basic solid wire, with minimal resistance, and a silicone jacket covered by a very necessary metallic ground jacket.
The "capacitor" is there, it is just akin to those "spark gaps" that JC Whitney used to sell that you clip onto plugs to help fire oily plugs - its main function is to provide some "resistance" since the wire are non-resistor and allow the voltage to build up behind it before discharging to the gap across the plug. Kinda like taking a hose, turning it on full while holding the end in a kink - when you feel the pressure, you can let go and you get a nice big splash out the end, more than what you would normally, for a short while anyway. It's not a bad idea, it just does not add any value to today's high voltage, microsecond switching ignition systems. Basically, these particular wires will work, but their Achilles heel is that they are highly dependent on having an excellent ground supplied to the wire's shield at all times or the EMF impulses will remind you, your car's ECU, your stereo and probably your neighborhood of how annoying (and probably malfunctioning to your car's electronics) spark noise is. Due to this glaring weakness, they are no better and probably worse than a standard OEM wire."