Spark Plug Lead Rebuild Plug End

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TFF

Well-Known Member
Joined
Apr 28, 2010
Messages
17,038
Location
Memphis, TN
My “doesn’t care” came from the tech rep verbally. He was answering that any resistance is ok because it’s not broken. Of course tempest gives a different answer. I treat champion like the tempest. Yes I have had bad champion but rare. I will go through my pile of spares if I find one way out, to match out a used set. Depends on need. A friend’s shop gave up on them. His volume was way more than mine. He didn’t change every plug that came through the door, but if there was ignition problems , the tempest went in.
 

JimCrawford

Member
Joined
Nov 30, 2019
Messages
24
Location
Oxford, UK
I've just started running my VW engine fitted with dual Leburg electronic ignition units. After a bit of a faff sorting the fuel priming it now starts on first compression and runs smoothly. My initial fit, running now, uses plain plugs and resistive cable but when I made up the cable I became a little concerned about the durability of the cable which uses a graphite loaded fibreglass core conductor.
Anybody have any opinion on this issue? Or should I simply play safe and replace with resistive plugs and copper cored cable?

Jim
 

Dana

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Apr 3, 2007
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10,760
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CT, USA
If you take apart an aircraft spark plug shielded lead, you'll find that in many of them the core wire is a stainless, tightly-coiled spring, and I think that's to concentrate the magnetic field within the core so less of the signal escapes.
Coiling the wire makes it a better inductor, which helps damp the fast transients while still showing very low resistance to DC.
when I made up the cable I became a little concerned about the durability of the cable which uses a graphite loaded fibreglass core conductor.
Anybody have any opinion on this issue? Or should I simply play safe and replace with resistive plugs and copper cored cable?
Auto plug leads last a long time.
 

proppastie

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Joined
Feb 19, 2012
Messages
5,596
Location
NJ
Automotive leads are resistor leads to suppress noise.
Why does adding resistance reduce noise...and I thought low resistance was what we were looking for when we test plugs (less than 5000 ohm?)
 
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