Aftermarket spark plug wires for 2.4L

High voltage wire is high voltage wire. The only variable is "resistance" wire vs. straight copper. I think just about all spark plug wire now has controlled resistance. It's probably cheaper than stranded copper anyway.

You get all sorts of marketing hype regarding color, insulator thickness, etc. Go for price; if there are any subtle differences, you won't be able to tell and your Dodge won't care.

Ken

snipped-for-privacy@sisna.com wrote:

Not really. There's also MSW (magnetic supppression wire) which is coiled solid wire. It is the best of all worlds - it relies on inductance rather than d.c. resistance to provide EMI/RFI suppression, yet has the high punch (low d.c. resistance) capability of solid (straight) wire conductor. And it is infinitely more durable than "resistance" (powder carbon) core wires - I avoid that stuff like the plague.

Probably everything uses silicone insulation this day and time, but you may sacrifice quality of that if you go bottom of the barrel for low price.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

If one were looking for this wire, what marketing buzz words would one expect to see on the packaging? Would "MSW" be it or are there others as well? BF

I think there will be "MSW" prominently mentioned on the packaging. Also you will typically see descriptive terms like "spiral wound solid core", and maybe a cutaway construction view on the back clearly showing the spiral core winding (like a long spring). I know the parts stores like Advance used to carry the Accel brand - probably still do. Accel makes both resistor core and MSW - make sure you get the latter. Available in your choice of colors - black, red, yellow, blue. Very high quality silicone insulation.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

A couple of companies make various plug wire products that are available on a roll, and the boots and ends and a crimper to put them on. MSW or stainless cannot be soldered. Copper can. I like to buy the roll product and terminate my own, but no retailer around me has it.

Thanks Bill, I'll file that info away. RapidRonnie, try farm tractor or truck supply houses for copper core wire. BF

From an electrical perspective: This makes sense. Of course, MSW should reduce any radiated static that affects radio fidelity and would have lower DC resistance, as you have noted. My understanding, however, is that the average driver would be hard pressed to discern any performance difference using resistance wire, stranded copper wire or MSW.

And it is infinitely more durable than

I don't understand why durability of resistance wire is an issue. My experience with failed spark plug wire is that a dielectric problem develops someplace, not a problem of continuity.

My '90 Miata and all Miatas are "tough" on spark plug wires. I suspect that it is directly related to the amplitude of the pulsed high voltage applied to the wires. They have a track record of failing every 30K to

50K miles or so. I have close to 200K miles on this car and have gone through several sets of wires. Sometimes I get to plan ahead, but usually I need to buy whatever is handy at the time when they fail. OEM, el cheapos....whatever...there is no difference in how long they last. For the reasons stated, my experience with various "grades" of spark plug wires make sense.

The only place I would advise caution is that some of the wire sets I have bought were "universal" in nature. This means that the lengths would, in some cases, be too long. It's probably more of an appearance issue than anything else. You can shorten the wires, but this is not advised for those who have no skill or experience making (or re-making) electrical connections.

This is sort of a hot button for me as I really hate to see people being spoon fed marketing hype that takes advantage of them.

Ken

Actually the Accel brand that I mentioned that many auto parts stores stock comes unterminated so that you can cut the 4 or 6, as the case may be, extra long wires that come in the kit to the correct lengths (using the old set as a template), and a crimping die is included in the kit for proper and reliable termination. Pretty much what you described, except the wires come pre-cut intentionally long rather than cutting off of a continuous roll.

There are other very good brands of MSW that come more or less cut to the proper lengths and pre-terminated at the factory. Those are more from mail order sources as the local parts stores would have to stock too many kit set variations (though they probably have them available from their warehouses for overnight shipment).

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

They would get a hotter spark (higher current and energy due to insignificant resistive loss) with straight copper or MSW wire. If a system is marginal, the reistance wire may give problems whereas the others wouldn't. I'm thinking of high compression or turbo under heavy acceleration where the high cylinder pressure raises the threshold for sparking.

However, resistance wire is definitely a limited life part. A good MSW set *will* absolutely last the life of the vehicle.

Funny that you say that - you often see incorrectly advised on various internet forums that all you have to do to test an ignition wire is to measure the resistance of the wire for continuity. I am always quick to point out that that does not check for, as you point out, the much more common insulation failure mode. And most people don't understand the difference.

I don't know that there is much resistance wire from the factory in vehicles now, so people don't experience that failure (lack if continuity) much anymore. I know from experience years ago when powder core wires were the mainstream, they were a definite wearout item due to the core itself - and that's when I got into the MSW wire for that very reason. And they (powder core) were totally unforgiving of the wire being pulled or handled roughly (core gaps/breaks). I think the incorrect advise about only checking a wire for continuity is left over from the days when resistance wire was the common type of "wire" - and that was overwhelmingly the more common mode of failure.

Hmmm - are you sure they aren't the powder core type? I would be willing to bet that if you started using a good grade of MSW wire, you would never have any more problems in that area. The good grades come with excellent insulation, and the core will never fail. They really shine on turbo-charged vehicles where insulation breakdown is more critical (due to higher cylinder pressure).

Yep - that is true. The Accel kits I mnentioned are not pre-terminated. They come with a crimping die, and you cut the sure-to-be-long 4 or 6 wires that come in the "universal" 4- or 6-cylinder kits to the exact length you want (typically using the old set as a guide - adjusting if old set was a poor fit), then crimp the ends on. Kind of the best of both worlds, IMO. I know they do it to cut down on different inventory part numbers, but it allows you to get the lengths right.

Hopefully you don't consider what I posted to fall into that category. I think you would see the difference if you were to try some Accel or other good brand MSW's (unless the Miata takes some weird wire ends that the aftermarket doesn't fool with).

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

MSW.They would get a hotter spark (higher current and energy due to

you often see incorrectly advised on various

I would be

not pre-terminated.

consider what I posted to fall into that category.

I appreciate all the interesting discussion on this. What is happening, is that the spark is arcing from the plug tip, to the plug base. Does this mean that the boots are worn, and that is why I need to replace the plug wires?

It seems like someone mentioned that some non-conductive lubricant could be put on the plugs to prevent arcing. The shop quoted me $65 for a new set of wires. NAPA has a set for $33.

Thanks again,

-KM

By "plug tip" in this case, I assume you mean the end that the ignition wire plugs onto (rather than the center spark electrode, which is commonly referred to as the "tip").

Absolutely you should be putting electrical grade silicone grease (also called dielctric grease) on the inside of the wire boot (ignition module/distributor end too) - that is assumed, and lack of it would certainly explain the problem you've been having. A light coating is all you need.

The grease closes up the microsopic gaps between the plug ceramic OD and the boot ID - the high voltage only needs a microscopic air hole (gap) to punch thru to find a ground to arc to. Once it arcs (ionizes), a carbonized (conductive) surface is created in the pin hole, and it rapidly gets drastically worse from there. The grease prevents the beginning of that whole process. If the boot slides on the wire OD, it would not hurt to also slide it back, put a light coating of silicone grease on the wire OD in the area the boot surrounds it when in place, and then slide the boot back into place.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')