Spark plug wire question

[nonamekid]

Will plug wires designed for the KLDE work on the K8? I have read that K8 spark plug wires will not work on a DE but I was wondering about the other way. Reason I ask this question, I need to buy some spark plug wires, but I also want to get a KLZE in the future. If I buy a set now, i want to know if I might be able to use them in the future. Thanks

[wytbishop]

I bought a set of Ractive 7mm wires for my K8 because they were cheap. They're not made for the K8, so the lengths are different than the stock set. The boots are correct though.

Functionally there's no difference...other than the claimed higher quality...which is debateable.

[fowljesse]

If you buy wires that are too long, they are pretty easy to shorten. I've shortened them on all my cars for the last 15 years, because I'm wierd. I like to believe that it improves the spark. I took 3 feet off my OEM GS wires. If anyone is interested, I'll put up a walkthrough with pics. I'm researching the possibility of buying a bulk 9mm kit, and making wires for my KLZE. I've made sets for other engines, but not OHC's.

[94drumx3]

yeah, you should be fine with gettin the ones ur wanting.

[wytbishop]

I've had the shortening plug wire discussion before. Speaking as a physicist, wire length makes no difference at all.

You probably don't care. But I felt compelled to comment.

[se7en]

hold on a sec....wire length makes no difference?

what about ohms....the longer the wire that I have measured the more the ohms.

usually most quality plugs wires are sold by "how much resistance they have per foot..."

I don't know, maybe it is just advertising hype....I will try to remember to measure a old junky plug wire at work, and then cut off half of it...and measure it again, and see if there is anything to this...


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[wytbishop]

Mathmatically yes the longer wire has greater resistance. The resistance in a current carrying wire is directly proportionate to the Resistivity of the material and the Length and inversely proportionate to the cross sectional Area.

Omega = R * L / A...as L increases, resistance increases.

In a continuous service RC circuit like a household load on an extension cord for example, that is significant because as the resistance (R) of the cord increases the current (I) in the cord decreases for the same voltage (V = I * R). If you plug your table saw into the wall using a 100 ft cord, you'll notice it spins up slower than if you use a 20 ft cord.

But your plug wire is not a continuous service circuit. At redline it sees so many pulses of current from the coil that it seems to the observer to be continuous, but it isn't. At 6000rpm, a large number of electrons (LARGE!!!) is dumped into the wire 100 times per second. But the wire isn't empty. The reason current carrying wires are made of copper and other very low resistivity materials, is that they have a natural abundance of "free" electrons. They're not actually free, they're floating around alone in the outer layer of the molecular structure of the material, so they're really easy to push out of orbit. So when a billion billion electrons are forced into one end of the wire, bombarding the material with energy, those "free" electrons are easily pushed off of the molecules they belong to to do the same to the next molecule in line...and so on through the wire. Think of a tube full of marbles. If I push a marble in one end, a marble has to come out of the other end.

That is why, from a physics perspective, the length of a spark plug wire is not very significant. Current does not "flow" in a spark plug wire, it moves in discrete pulses. Yes the resistance will be higher, but the speed with which the electric charge propegates through the wire will not be measureably affected.

Having said all that, you would get spark faster out of a 1ft plug wire than a 50ft one...but not much faster.

[94drumx3]

ah, behold the power of physics!

[Raven95150]

At 6000rpm, a large number of electrons (LARGE!!!) is dumped into the wire 100 times per second.

With all the technical speak going on here, I figured I should make my own technical correction.

The plugs fire every other revolution, so at 6000rpm they would only fire 50 times a second.

I know, this really doesn't change the point, but by correcting someone with a much higher education than myself at least I can feel smart for a couple minutes.

[wytbishop]

yeah well I only sound smart so it's fine.

[azgtx]

Ben..This is off topic but since maz323 went down haven't been able to stay in conact...do you still have that tranny?
Conact me at azgtx@yahoo.com" onclick="window.open(this.href);return false;
Thanks
Clay