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Guest Message by DevFuse

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Does spark plug wires' LENGTH matter? Nope - it doesn't. Thanks

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4 replies to this topic

#1 wtdash


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Posted 06 July 2010 - 11:27 PM

DA of the day award: Didn't label the wires when I pulled them to swap the engine.

The OEM replacements aren't labeled either. There are 2 the same length and the other 2 are both different lengths - one is much longer than the others.

Does it matter where they go as long as the right port on the coil goes to the correct cylinder's plug?

I've searched and either it's not here or using wrong search terms.

I remember my Dakota's V8 had a different length wires and they had to go to the correct cylinder from the distributor....so just checking.


Edited by wtdash, 07 July 2010 - 10:05 AM.

#2 3eyedwagon


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Posted 06 July 2010 - 11:53 PM

The ones on your Dakota "had to go to the correct cylinder" because they had to reach each plug correctly. If you mix them up on a v8 you'll often end up with some that don't reach, and others too long for where they are. There weren't special wires for a certain cylinder, just ones cut to the length to reach THAT spark plug.

Other than that, it doesn't matter. Just route them the best you can in relation to which length is needed to reach from the distributor to the plugs. That's why they make them different lengths, and not all just really long. That way you don't end up with a pile of excess plug wire sitting on top of the air cleaner.

#3 idosubaru


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Posted 07 July 2010 - 10:03 AM

no, it doesn't matter.

electricity travels the length of the spark plug wire in 0.000000003 seconds, so a few miles probably wouldn't even matter at those speeds!

#4 wtdash


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Posted 07 July 2010 - 10:05 AM

Thanks guys....appreciate the replies.

#5 Allpar Mod

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Posted 08 July 2010 - 01:16 PM

The only thing excess length on wires is of concern is if they contact parts that may cause chafing or get burned from the movement and vibration of the engine. Make sure the wires stay away from the block and other assorted parts.

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