Plugs and Wires

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bobscuda67

bobscuda67

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Can someone educate me on the subject of spark plug wires and the plugs.
Right now I sent my distributor to FBO to be recurved for the new cam I installed. While I'm waiting I went and checked all my wires and plugs. I checked my wires with an ohm meter and it showing I have about 6k ohms per foot resistance. Which is normal for the 15 year old carbon core wires that I'm using.
The plugs are NGK's resistor plugs with a 1k ohm resistor in them. Needless to say I have no RFI problems.
What would happen if I installed solid wires? Would the plugs be enough to suppress the RFI?
Would there be any noticeable difference in the way it runs?
Also, is there any advantage to use a projected nose plug?
Thanks for any info you can share.
 
Typically use non resistor plugs with resistance cables. I did some tests using my igniton coil tester with a Champion resistance plug I bought by mistake, the spark was much weaker in intensity than standard plug. The added resistance decreases spark current, and also decreases spark duration. Your Ohm meter test does not measure insulation leakage, that is important too.

With electronic ignition, best not try to use solid wires. I have used solid wires with resistor in rotor, and at plug ends, but resistance cables radiate much less. The solid wire radiates, the spark energy is frequency rich, with various lengths of plug wires, you will be broadband jammer. There are wires with spiral core and semiconductive shields. I use reasonably priced cables, and change frequently.

Use spark plug designed for you engine, and heat range. Projected tips are higher heat, in miss application, plug may hit piston.
 
Solid wires / R plugs will likely cause radio noise

Some ignitions do not recommend solid wires. I believe this has more to do with radiated interference than anything else. That is, some modern ignitions "bang" the spark pulse so hard that they generate a powerful electromagnetic pulse, made worse by solid core wires. This radiated power can interact with other systems, not excluding voltage regulators, EFI, or just about any other electronic system. They can also cause false triggering of the ignition system itself

I would not use a projected plug unless the application catalog for that engine recommends one
 
I am running NGK FR5 plugs and MSD 8.8 Super conductor wires. I have an AM only radio in my duster, so i am sure it will be a pleasure. lol
 
Most plugs now adays are resistor type, and for a street car run a spiral core type wire.
 
Thanks everyone, just asking if solid wires are feasible or not. I'll just buy the spiral core wires, but I think I'll go with a non resistor plug.
A broadband jammer, that could be fun!
 
Bad Sport said:
They are illegal to run in some areas.
Click to expand...

They are illegal ANYWHERE in the U.S. All this is under FCC jurisdiction, and I can assure you that it's highly illegal.

Now, I WILL admit that in the last 20-25 years, with the FCC becoming more politicized and less technosized, it might be an aging tiger with his teeth falling out, but it IS still illegal

Actually, new cars DO have to meet FCC interferance regulations, even though in some cases they can be "troublesome." Toyota, years ago, was particularly non cooperative. Very common, with vehicles and two-way installations.........to see additional supression measures, groundindg / bonding on hood, doors, exhaust etc and additional filtering here and there

When I had my Mom and Dad's 86 Dodge 600 (K car) after Dad died, I was still active on amateur radio VHF / UHF. The damn EFI system in that car had a substantial "birdie" right in the middle of the 2- meter amateur band. I think it was 146.52 MHZ which is supposed to be the "national calling frequency." So naturally, I had it in the "scan list" of the radio.

A very quick look with an r.f. spectrum analyzer will show just how dirty some of this stuff really is.
 
In mathmatics there is something called an infinite impulse function. It has an infinite amplitude, for an infitesimal period of time. If a fast Fourier transform is used to analyze the impulse, it contains an infinite spectrum of frequencies. A spark is similar, it has a high amplitude for a short period.

An antenna is a conductor, it radiates RF energy well, if the antenna length is a multiple of half the signal wavelength. So with the various lengths of plug wires, there is an enormous chance the radiated noise will be undesirable at a huge number of frequencies.

That is my story and I am sticking to it. :)

It is one reason why modern ignitions are direct fire, coil on plug, elimating plug wires, and open spark gaps.
 
KitCarlson said:
if the antenna length is a multiple of half the signal wavelength. So with the various lengths of plug wires, there is an enormous chance the radiated noise will be undesirable at a huge number of frequencies..
Click to expand...

Actually it's much worse than that, and I don't even understand the math, LOL

1/4 wave is what makes a radiator in a situation such as a plug wire, and it doesn't even have to be 1/4 wave. All it has to be is long enough that the impedance is great enough to allow RF voltage to climb at the far end of the radiator enough to cause the "damage." Since we are talking about such short distances, IE, LOL we are not Marconi in the "spark" days trying to hear the Titanic, LOL

This is allegedly an authentic photo of the Titanic's radio room



The Olympic's radio room, Titanic's sister ship is often pictured, but it is claimed that Titanic's radio room was actually quite different in layout

From the James Cameron movie. Isn't this a warm, cozy place? Hell, THIS could never sink

radioroom.jpg
 
Dell, You are correct, 1/4 wave and ground plane... loops and nodes.
What I always think is neat about RF, is that is composed of transverse electric field and magnetic field waves 90 degrees apart. The math came long before the discovery of RF.

I saw a video about Tesla on netflix, he invented tuned RF spark gap radio receivers and transmitters long before Marconi. Marconi copied his work and submitted patents without even a good understanding.

Tesla reported he received a signal 1-2-3... Over and over, and suggested it could have been alien, Think of how that would have been, to have a receiver in a near at the time of pre electricity and earthly transmitters. Now days with all the RF, signals and noise, we no longer have the ability to hear ET. At least close to earth.
 
KitCarlson said:
Now days with all the RF, signals and noise, we no longer have the ability to hear ET. At least close to earth.
Click to expand...

Hell I can't even hear the guys in Portland and Seattle on 160 meters on most nights...............

Our toothless FCC................
 
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