>> High voltage wire is high voltage wire. The only variable is
>> "resistance" wire vs. straight copper. I think just about all spark
[quoted text clipped - 6 lines]
> yet has the high punch (low d.c. resistance) capability of solid
> (straight) wire conductor.
>> 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.
> 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.
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.
> And it is infinitely more durable than
>
[quoted text clipped - 4 lines]
> experience with failed spark plug wire is that a dielectric problem
> develops someplace, not a problem of continuity.
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.
>> Probably everything uses silicone insulation this day and time, but
>> you may sacrifice quality of that if you go bottom of the barrel for
[quoted text clipped - 9 lines]
> For the reasons stated, my experience with various "grades" of spark
> plug wires make sense.
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).
> 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.
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.
> 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.
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')
kmatheson@sisna.com - 22 Jan 2007 16:54 GMT
> >> Not really. There's also MSW (magnetic supppression wire) which is
> >> coiled solid wire. It is the best of all worlds - it relies on
[quoted text clipped - 82 lines]
> (To reply by e-mail, replace the last letter of the alphabet in my
> address with the letter 'x')
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
Bill Putney - 22 Jan 2007 19:10 GMT
> 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...
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").
> Does this mean
> that the boots
[quoted text clipped - 3 lines]
> could be put
> on the plugs to prevent arcing...
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')