Author Topic: Misbehaving plug wires  (Read 4268 times)

Offline Spud Miller

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Misbehaving plug wires
« on: July 30, 2018, 09:44:12 AM »
 Since someone brought it up in another thread...I have MANY Promag "bad plug wire" stories this season so far.

 Behavior that you'd never suspect and it's the suppression core race wire that the electronic mags require. People don't understand that it wears out! It looks perfectly fine and good but electrically, it's a nightmare. It might check out fine and seem normal with the ohm meter, but when they're changed out for a new set, everything is happy and normal again. Even if you can't explain why, it's difficult to argue with results!

 So, if your Promag ends up having strange timing and phasing issues that don't make sense, timing lights freaking out, points boxes not working right...save yourself some time and change the plug wires first!

 Spud

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Offline 32bantam

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Re: Misbehaving plug wires
« Reply #1 on: July 31, 2018, 04:44:16 AM »
AMEN !!!!!!!!!!  Just went thru that with Gary O Connells car !!!!!

Steve Walczak

Offline wideopen231

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Re: Misbehaving plug wires
« Reply #2 on: July 31, 2018, 09:43:13 AM »
Guessing noway to check other than swap out. Sucks because normally one wire bad,plus I have 4 or 5 old sets.Not that anything was wrong with them,just maintenance swaps.   OP said super mag issue and figuring same thing with MSD mags.
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Offline Spud Miller

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Re: Misbehaving plug wires
« Reply #3 on: July 31, 2018, 09:51:52 AM »

 Nope this isn't a Super-mag issue...this is only with Pro-mags. They are VERY sensitive to bad or overused wires due to the solid state components in the points box.

 In the situations referred to, the wires tested good. But they were the problem.

 Spud

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Offline Paul New

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Re: Misbehaving plug wires
« Reply #4 on: July 31, 2018, 11:51:03 AM »
I wonder if a Insulation Megger would find the insulation bad and show something?

Offline Spud Miller

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Re: Misbehaving plug wires
« Reply #5 on: July 31, 2018, 12:01:04 PM »

 The insulation isn't bad...it isn't shorting out anywhere. There aren't any dropped cylinders, instead it messes with timing in a big way which is a delay function and related to the smarts in the points box. And it isn't just a timing light phenomena in the pits...the cars really RUN BAD. So the timing strangeness is real. It's a mystery.

 Spud

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Offline Paul New

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Re: Misbehaving plug wires
« Reply #6 on: July 31, 2018, 01:03:19 PM »
Interesting?  There would have to be some sort of test I would think?

Offline wideopen231

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Re: Misbehaving plug wires
« Reply #7 on: July 31, 2018, 02:39:46 PM »
My bad on pro mag part/ So I guess I  might as well add new wires to list of need to have now. Running out of lines,going to have to flip paper over.LOL
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Offline wideopen231

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Re: Misbehaving plug wires
« Reply #8 on: July 31, 2018, 02:42:09 PM »
Is this just a issue lately.Like maybe something in manufacturing of wire? Asking Because I have cpl sets on shelf that are old but never used and wondering if should use those or just buy all new.
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Offline gregm784

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Re: Misbehaving plug wires
« Reply #9 on: July 31, 2018, 02:57:01 PM »
Is this why you started selling the Taylor wire Spud? i still have a couple sets of new MSD wires.  Should i be switching to Taylor?
Greg
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Offline Spud Miller

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Re: Misbehaving plug wires
« Reply #10 on: August 01, 2018, 09:51:43 AM »

 I'd never seen these types of problems before a few months ago, but it could be a change in the points boxes too. Every one of these cases was indeed with MSD wire, but I have no reason to believe it couldn't be a problem with other brands of similar wire. All brands of suppression core wire wear out with use eventually.

 There were quite a few reasons for us switching to Taylor wire, but probably none of which would be the culprit in this case.

 I wouldn't be a bit afraid to use your brand new sets of MSD wire.

 Spud

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