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ok, from what i have read the thickness of the wire means nothing, because its just the rubber that is thicker and the actual core of the spark plug wire is the same so in fact what are the ohms? more is better? and following that what is a good spark plug platinum spit-fires or ???????? i was thinking about going with the screaming demon but how can this inmprove performance. i mean my stock coil does the job so what would another coil do better for my vehicle?
 

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Ohm is resistance to current. Just look at ohm's like a water pipe and current(the charge from the coil) as the water.
Higher the ohm's value, smaller(more resistance) the diameter. Smaller the ohm's value, the larger(less resistance) the diameter.
So when you have less ohm's, it allows most of the charge from the coil to reach the spark plug. Higher the ohm's value causes some of the charge from the coil to get lost in the spark plug wires. Hope this helps. [?|]
[whip]
 

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I remember when the MSD wires first came out... they advertised something like 40 ohms per foot of wire. I had a Supercharged '93 Cobra at the time, put those wires on, and in like a month my car was running like shiit. It was sputtering and I never thought 1 month old plug wires would go bad... after changing a few things (wasting time and money) I finally decided to change the wires and that fixed it. Those wires weren't cheap either! I'm sure their wires, and others like theirs, are better these days but it'll always be a thought in my mind when I buy aftermarket wires that claim low resistance.
 

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Mr. Wizard
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I'm 100% positive that the wire covering isn't what is thicker. Otherwise it would make NO sense whatsoever, unless to protect your stereo components from interference. (Which shouldn't be an issue anyways.) The wire is thicker diameter, so lower resistance, if your plugs aren't gapped right, your car could run like crap with new wires, where as it may not matter so much with the current wires. Your coil will still send out the same amount of discharge regardless, but more of it will get to the plug. As far as Banshee's experience...sounds to me like perhaps the coil was hotter than the wire was prepared for. Otherwise there is no electrical reason that new wires would burn out or work any less than stock. If I had to guess I'd say that it was something to do with the coil...(or distributor cap maybe on the '93), my brother has a 92 exploder errr..explorer, and the distributor cap went and caused similar problems. No telling if I'm right or wrong, just other ideas.
 

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. i mean my stock coil does the job so what would another coil do better for my vehicle?
Modern ignition systems are pretty fantastic at what they do. It is hard to find any real hp gains just by upgrading the ignition, unless you are feeding tremendously increased air and fuel loads into the cylinder ala focred induction, and even then I doubt it would be a neccesity. I think you would be happier with cam gears and a dyno session, if you are looking for a place to drop some coin. My understanding on wire size is that both the inner core and jacket increases, to allow for more currennt flow and adequate radio suppression. Side note: Porsche uses wire with almost 0 ohms in combination with Beru connectors to provide resistance. This way every wire has the same resistance no matter the length for consistent current flow. Oh, to have the details found on 80 grand cars.
 

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The insulation on the wire has a little to do with wire resistance. It does have an effect in the sense that heat changes the resistance of the wire. Thinner insulation can permit inductive and/or capacitive effects by surrounding wires. Also, damaged insulation can cause surface losses, in the worst case, shorting out of the lead.

It is the thickness of the core of the wire that has alot to do with it, as well as it's construction, ie multistrand or solid core. Another factor to resistance is the material used.

Voltage is dropped over resistance, as the current passes thru it. So the smaller the resistance in the wires, the smaller the voltage lost, the higher the voltage you'll have at your spark.

Realistically, high tension ignition wires should not provide much of a loss these days, at all. Someone mentioned 40 Ohms per foot of wire, a resistance like that is huge, we'd be replacing that at my work if we found any today.

I work in Avionics in the Air Force, we do alot of this wiring type stuff.... fun eh! [;)] [hatchet]

Hope that helps at all, but sounds like everyone knows what is going on!

Cheers........ Tim
 
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