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Here's a puzzler for you

Posted: Thu Sep 18, 2008 9:26 pm
by zmwworm
I heard a rumor that if you buy considerably longer spark plug wires for a car, then wrap them into a coil shape somehow that you can get better gas mileage/more power (just like the fancy spark plugs are supposed to do, I guess). What, if any, circumstances would starve a spark plug, and could also be remedied by a coiled plug wire? I don't have a lot of electronics knowledge, but this sounds like making an inductor to me. Anyway, what are the forces at work in a setup like this?

Posted: Fri Sep 19, 2008 3:10 am
by jwax
"Forces at work"? Unfounded claims are at work here.

Posted: Fri Sep 19, 2008 4:13 am
by dacflyer
sounds like a bunch of quackery to me
just coiling up a wire will do nothing,,you'd have to have tons of it to make any worthwile inductor....

Posted: Fri Sep 19, 2008 7:44 am
by MrAl
Hi,


Inductors in series add. Adding a small inductor in series with the
ignition coil increases the total series inductance. This could cause
more ringing or a longer spark time.
The thing is though, the ignition coil inductance has got to be quite large
by itself and so any air core inductor is not likely to add much inductance.

There might be some benefit as to lower the RFI to nearby equipment, or
because of the increased wire length it might actually increase it. It could
also change the frequency band.

Posted: Fri Sep 19, 2008 2:49 pm
by philba
I suspect that the added inductance is barely measurable.

This is just another in a long list of nutty claims that people make. Like the car that runs on water (browns gas, HHO, blah, blah, blah). Next we will probably hear that the evil oil companies or government suppressed this idea.

Posted: Fri Sep 19, 2008 8:25 pm
by Dean Huster
I would suspect that if you used cables having low-oxygen copper that was braided and had gold plated connectors, you'd have a LOT better performance. Hey, if it works for the audiophools, it ought to work for cars.

Dean

Posted: Sat Sep 20, 2008 1:00 am
by MrAl
Hi again,


Dean, i see where you are going with this so i have to think that
because the current is more or less a pulse and a pulse has significant
energy in higher harmonics, perhaps some Litz wire would help. At
least the ac conductivity would improve :smile:

Another idea would be a tubular wire shape like the ground shield
in an audio cable. In fact, an audio cable with better outside
insulation.

Posted: Sat Sep 20, 2008 4:07 am
by jwax
Or 1/4" copper tubing (like the condenser coil on a still).
Probably have to mount them on top of the hood to prevent cross-fire, but hey- if it's going to improve performance....I say go for it.
You would have to look through the coils to see where you're efficiently going however.
:razz:

Posted: Sat Sep 20, 2008 8:33 am
by MrAl
Hi,

John, when i am traveling on the highway and i cant see in front of the car
properly and smack up into the car/truck in front of me i like to do it as
efficiently as possible :smile:

Posted: Sat Sep 20, 2008 8:57 am
by reloadron
I would like to think that when the ignition system was designed they considered the efficiency, including the wires.

However, the theory reminds me of a myth from lond ago. When cars actually had real hub caps before whatever it is they have now, that placing aluminum foil in the hub caps would prevent getting a ticket from that then new RADAR police used to measure your speed. :smile:

Discounting all electrical & electronic theory I see the concept of using longer ignition wires and coiling them as more urban legend than a practical approach to fuel economy.

Ron

Posted: Sat Sep 20, 2008 4:56 pm
by Robert Reed
Zmworm
" What, if any, circumstances would starve a spark plug,"

From the '50s thru the '80s when plugs were gapped at ~ 0.03", they would fire at 5000 volts across them and it didn't matter if your ignition system had the capabilities of 50,000 volts output, it would still clamp at 5000 volts when the plug fired. For radio interference suppression in boats (and some cars) where there was no metal shielding (i.e. hood, fenders etc.) between the ignition system and antenna, 10 K resistors were installed in series with each lead. These were special holders with the proper clips to snap from plug to wire and they limited current flow upon firing thus reducing EMI radiation. From the '80s to present, higher voltage ignition systems became common in cars and the plug gap was widened to 0.06" .These new gaps required a higher arc-over voltage, but doubt if they reached 10K volt. The discrete resistors were replaced with resisance wire of about the same ohmage. I havn't kept up with changes for a few years, so they may be doing something completely different now. But my point being that even increasing lead resistance had no effect on engine performance and a properly operating plug will always fire well below any "hi voltage" ignition ststem out put. Most of that is for marketing hype anyway. I have installed many of these suppression circuits on marine engines over the years and had no effect whatsoever on engine performance, but they did accomplish their task of reducing RFI to the marine radio.
Now given that an 8 cyl. engine running at 6000 RPM will only require an extremely slow pulse repetion rate of several hundred ignition pulses per second, I can hardly see where pulse rise time variations would even enter into the picture. I have tried to analyze the coiled wire set up from several aspects and cannot come up with any electronic explanation for doing this. Probably another J C Whitney gadget like the carburetor air horn mounted muffin fan that would super charge your engine. The one good feature about that method is that it sell more yards of wire for the manufacturer. :grin: The only coiled wires I have ever encountered in ignition systems were in the primary sides of coils and generator related wires on marine engines, again as an attempt to reduce RFI.

Posted: Sat Sep 20, 2008 6:28 pm
by zmwworm
Robert Reed wrote:The one good feature about that method is that it sell more yards of wire for the manufacturer. :grin:
That's about what I figured. You have to wonder how these rumors get started...

paser magnum

Posted: Thu Sep 25, 2008 6:20 pm
by frhrwa
back in the 60's, there was a thing called the paser magnum.. ha ha ha.. it was a set of plugs that looked like the top of your distributor, except each one was wired to the next and cut at the end, so if 8 cylinders, 8 tied together, and so on.. it was supposed to pick up an inductance from the firing of each spark plug, induce a potential into the other cylinders via the other spark plugs, thus creating a + potential, then the fuel would come in at - potential and immediately be sucked all over the cylinder in order to get a better fire, better gas mileage, and more power.. anyway, that was what was supposed to happen..

Posted: Fri Sep 26, 2008 7:40 am
by dyarker
That one almost makes sense. Don't see where gas being attracted to cylinder walls would do much, but charged gas molecules would repel each other. Giving better chance to be near an oxygen molecule as flame front moves outward from spark plug.

Cheers,

Posted: Fri Sep 26, 2008 12:26 pm
by philba
reloadron wrote:I... reminds me of a myth from lond ago. When cars actually had real hub caps before whatever it is they have now, that placing aluminum foil in the hub caps would prevent getting a ticket from that then new RADAR police used to measure your speed. :smile:
...
Ron
there was a theory that it would induce a doppler shift and cause the radar gun to receive false signals. Silly. I think if there were tuned reflectors that were presented on the bottom half of the wheel (the part with lower relative velocity) but not the top the strong, slower echo would overide the echo from the vehicle body. A lot of ifs.