Which spark plug wires?

March 4, 2008 5:33 PM

I'm looking for a reasonably neutral comparison of various brands of spark plug wires (ignition wires). Specifically, I want to know if there are strong advantages over name brands vs Autozone's house brand (Duralast).

I've found this vendor's description of some of the marketing hoo-hah behind some premium brands, and this objective but misguided comparison of the low voltage DC resistance of the wires.

Where are the tales from the real world of drivers that used the cheap-o Autozone wires and loved them, or who ran the cheapo wires and the expensive wires and had reasons to prefer one or the other? I would like to avoid the Monster Cable effect where people feel that the cables are great without anything objective to back it up.

I'm interested specifically in the following:

- durability of the wire - how well does it hold up over time?

- "performance" of the wire - delivery of spark, resistance to arcing, resistance to generation of EMI/RF

I'm hoping the hive mind can help me because, for once, I've struck out on the internet. Perhaps there's a car magazine that's done this comparison, but Google isn't helping me here.

Don't know if it matters, but the car is a 1996 Caprice Classic with a 5.7l/350 LT-1 V8 Engine.

posted by zippy to travel & transportation (8 comments total)

Less than two years ago, I installed Duralast spark plug wires on my '93 Mazda. Last week, my car started firing on three cylinders. Wasn't the distributor cap, wasn't the plugs, wasn't the rotor -- I replaced all three, but not the plug wires, because the guy gave me the wrong plug wire box -- but when I changed out the wires, the car ran fine again.

This is only one person's experience, and the new wires are also the house brand, but I think a year and a half from a set of spark plug wires in Southern California is terrible, and will be ordering the dealer wires shortly so I can forget about new ones for a while.

On the other hand, the first set of Duralasts was half the price of the dealer's wires.
posted by davejay at 5:41 PM on March 4, 2008

Buy the middle to high set of wires, because then you can leave them alone for 3 years or so. Plug wires should be replaces no less often than that anyway - there'll be a performance implication long before you notice it.

Never, ever buy cheap electrical items for cars. They will never save you money in the long run.
posted by Brockles at 5:49 PM on March 4, 2008

To be more specific, the relative durability of the wires is entirely subjective and related to the environment the car is kept in, the style of usage (long periods of hot running, lots of cold start etc, car specific installations) and no wire should go more than three years without being replaced - even if it is 'still working' if you want optimum fuel economy and performance.

So any anecdotal evidence is moot if you want (which it sounds like) to ensure good performance and trouble free running for a reasonable period, as it just as likely the other experiences are not directly comparable. I've replaced oodles of plug leads, and also just as notably not replaced oodles of them. Just like wiper blades, they are the things that I finally replace and go "Why didn't I do that earlier?".

Weak spark can cause other (more expensive) parts to have to compensate, or be affected by the poor running. If there is a failure or drop in performance, this is likely to cost you as much, of not more, then the difference between stock and a middling 'performance' silicone plug lead set. Think of it as insurance and piece of mind. Servicing is generally preventative maintenance, and a reasonable extra investment will pay off in reducing chances of trouble occurring.
posted by Brockles at 6:01 PM on March 4, 2008

In the not answering the question but trying to help with anecdotes vein:
I used the Magnecors once because they were half the price of OEM Bosch wires. They worked fine.

If you want to economize but you're hesitant to use the Duralast wires, check out Napa's Belden wires. They are (or they were, at least) very substantial, guaranteed forever, and cheaper than the dealer part.
posted by Kwantsar at 7:07 PM on March 4, 2008

I've been finding that many of the parts available at any of the retail auto parts places have been of miserable quality. As a data point, I have found that Autozone's house brand is among the best (Duralast, not Valuecraft). I installed their wires in my car (a supercharged engine), and was impressed with their quality and performance. On the other hand, their brake pads were hit and miss- one set was fine, another set was awful.

For the price, it's worth trying. I don't think you will see that much of a performance difference between that and Super Amazing Fantastic brand wires for twice the price. If you're going to spend that much money, get the OEM wires from the dealership. My experience has been that dealership parts are the best if you're willing to pay the price. Chances are, the wires that are on there came from the factory and lasted this long.
posted by gjc at 8:11 PM on March 4, 2008

Please keep the answers coming. I'm finding this very helpful in sussing out what I should get. I'm also curious whether anyone like Consumer Reports has done a study (long-term, ideally) on which brands are reliable.

And is it unreasonable to imagine that many of the ignition wire brands are actually made by a handful of companies? As one (admittedly weak) data point, the Car Quest plugs have identical boots to the Autozone ones.
posted by zippy at 12:42 AM on March 5, 2008

plug wires, that is.
posted by zippy at 12:44 AM on March 5, 2008

So many good answers - thank you, hive mind.
posted by zippy at 1:41 PM on March 5, 2008