Plug Wire Durability?
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Lead Driver
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Plug Wire Durability?
Anybody have a favorite brand of spark plug wires to recommend? I've had several sets fail and am about to tear my hair out, at least what's left of it. Actually, I still have all my hair, but unfortunately most of it is in the shower drain and of little practical use to me, but already I've digressed.
The failures are all the same. The conductor breaks next to the crimp at the plug end. I ALWAYS use plug wire pliers to remove them, so am not just yanking on the wires. And I rarely have to remove them, so it's not like I'm wearing them from removal and installation.
Heat from the exhaust may be a factor, but I've got stock manifolds, not headers. The manifolds are aftermarket replacements and are slightly beefier than stock, so the original sheet metal heat shields won't fit. I tried some braided silicone sleeves with one set, but it made no difference.
The brands that have failed are AC Delco, Motorcraft, and NAPA Premium. All had 45 degree silicone boots at the plug ends. Engine is an '84 351W with Duraspark II. Thanks for any recommendations.
The failures are all the same. The conductor breaks next to the crimp at the plug end. I ALWAYS use plug wire pliers to remove them, so am not just yanking on the wires. And I rarely have to remove them, so it's not like I'm wearing them from removal and installation.
Heat from the exhaust may be a factor, but I've got stock manifolds, not headers. The manifolds are aftermarket replacements and are slightly beefier than stock, so the original sheet metal heat shields won't fit. I tried some braided silicone sleeves with one set, but it made no difference.
The brands that have failed are AC Delco, Motorcraft, and NAPA Premium. All had 45 degree silicone boots at the plug ends. Engine is an '84 351W with Duraspark II. Thanks for any recommendations.
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Joined: Nov 2007
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From: Denver Metro Area, CO
I've had Belden 8mm on my truck for lots of years without problems.
If I were you, I'd next try AC Delco, or maybe something from Summit Racing or Jegs. Maybe NGK or some such.
If I were you, I'd next try AC Delco, or maybe something from Summit Racing or Jegs. Maybe NGK or some such.
Logistics Pro
Joined: Jun 2017
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From: Edmond, OK
You can get stock spark plug wires from the auto parts store with a lifetime warranty. That way, if they fail you can swap them for a new set.
I've had good luck with the "fabricate your own" kits available at Summit and Jegs. Just make sure you get a set of ratcheting crimpers with the proper jaws to crimp the ends.
https://www.summitracing.com/search/...asummit-racing
Never found a use for them on my truck though...
I've had good luck with the "fabricate your own" kits available at Summit and Jegs. Just make sure you get a set of ratcheting crimpers with the proper jaws to crimp the ends.
https://www.summitracing.com/search/...asummit-racing
Never found a use for them on my truck though...
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Lead Driver
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https://www.napabelden.com/index.html
This is the most recent failure, installed about one year ago. I wonder if Belden has recently cheapened their manufacturing process, as they seem to be highly recommended.
FTE Legend
Joined: Nov 2015
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From: Angier, NC
What are you doing, pulling the wires off 3 time a day?
How do you know they go bad or you removed them (again why?) and it broke when pulling the wire off?
My wires & plugs were installed 5+ years ago and have not needed to pull a wire off a plug so what gives with you?
Dave ----
How do you know they go bad or you removed them (again why?) and it broke when pulling the wire off?
My wires & plugs were installed 5+ years ago and have not needed to pull a wire off a plug so what gives with you?
Dave ----
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From: Angier, NC
Carl can take it 
I just cant see how they can break when they are on the plug.
How did he find it and them only being a year old?
I know sometimes the boot can be a bear to get off the plug but I twist the boot and they come off.
Dave ----
I just cant see how they can break when they are on the plug.
How did he find it and them only being a year old?
I know sometimes the boot can be a bear to get off the plug but I twist the boot and they come off.
Dave ----
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Lead Driver
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This last time, I had a light misfire present on a year-old Belden set. I did a cylinder balance test by pulling the distributor ends one at a time. I had not touched the plug wires at all since installation last summer. Two adjacent cylinders had no effect when disconnected. This concerned me, thinking it might be a bad head gasket. When I pulled the plug end of the wires, once again the terminals were found broken. As always, I'd used plug wire pliers to grip the boot.
I'm at my wits' end, as these seem to be quality sets. I've tried several different brands. I've consistently had some kind of misfire appear BEFORE I've pulled the wires, so I don't see how I'm killing them. In all cases, new plug wires cured the misfiring, at least for a year or so.
Mountain Pass
Joined: Oct 2016
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From: Saskatoon, SK
Working at an automotive shop, NGK is absolutely the way to go. MSD seem to be good as well, but not readily available. We always go for Belden if NGK isn't in stock, but their ends like to come off, even when new. I love the Ford Racing ones on my '86, not sure if they make those anymore.
FTE Legend
Joined: Nov 2015
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From: Angier, NC
I have heard of the plug end of the wire slipping off the plug because of the silicone grease they put on the wires but I have not had any break like that.
You said they were 45* plug ends what if you went with 90* ends or if they will fit straight ends.
I have never used a set of wires with 45* ends so wonder if that is why they are failing?
Dave ----
You said they were 45* plug ends what if you went with 90* ends or if they will fit straight ends.
I have never used a set of wires with 45* ends so wonder if that is why they are failing?
Dave ----
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From: springfield Missouri area
I have started using these,
https://www.oreillyauto.com/detail/c...?q=10083&pos=0
They are straight boots though. They have ceramic ends.
Also make sure you have the wires routed correctly. 2 of them on a 5.8 will crossfire. can't remember which ones.
https://www.oreillyauto.com/detail/c...?q=10083&pos=0
They are straight boots though. They have ceramic ends.
Also make sure you have the wires routed correctly. 2 of them on a 5.8 will crossfire. can't remember which ones.
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Lead Driver
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I could possibly use straight ends but #8 is pointing towards the firewall and would require a sharp bend. #1 might also require a sharp bend to clear the heat riser tube, but I’m not sure.