| Author |
Message |
Bill Bode (Guillermo)
New member
Username: Guillermo
Post Number: 1
Registered: 8-2003
| | Posted on Friday, September 05, 2003 - 10:28 pm: | |
Radio frequency interference (RFI) due to automobile ignition systems can be a considerable problem for your own vehicle radio or that of anyone near your vehicle. Resistor plugs and wires will lessen this problem. The carbon type wires have a central core of synthetic filaments that are impregnated with powdered carbon as the conductor. These frequently have a resistance of about 5K to 10K ohm per foot (30 cm). The problem with this type of spark wire is that with age, the carbon can separate slowly and cause their resistance to increase until they will fail completely. Before this time it can cause intermittent ignition problems, even thought the cable appears good externally. Solid non-resistance metallic wire will have a very low electrical resistance below 100 ohms depending on whether the wire is of copper, nichrome, etc. However, this solid straight wire will produce terrible RFI. I have been using the inductive wire (some called "Magnetic or Inductive Suppression" wire) which consists of a fine steel or nichrome wire wound helically (spirally) around a central non-conducting core for many years. This provides high impedence to the transmission of the higher radio frequencies but has a relatively low DC resistance. Usually on the order of 700 ohms per foot. Resistor spark plugs generally have an internal DC resistance of 5K to 10K ohms, though I have measured them as low as 3K ohms and as high as 20K ohms. I have been very pleased with the helically wound inductive RFI suppression wire with resistor spark plugs. I have excellent RFI suppression, and the helically wound wire is extremely resistant to breakage due to flexion of the spark cables.
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mike 308 (Concorde)
Member
Username: Concorde
Post Number: 288
Registered: 8-2002
| | Posted on Tuesday, September 02, 2003 - 5:50 pm: | |
If you're running solid core wires, couldn't you run resistor type plugs to help with your radio static problem? |
Kurt Kjelgaard (Kurtk328)
Junior Member
Username: Kurtk328
Post Number: 213
Registered: 3-2001
| | Posted on Tuesday, September 02, 2003 - 8:51 am: | |
Richelson, your numbers looks OK.
There are, however, different types of wires around and therefore different values
- the most important thing as I see it is
that you don't have big differences between them.
And that none has extremely high or unlimited resistance.
"Coil was 3.1" you say - KOhms? What car do you have? |
Russ Gould (Russ)
Junior Member
Username: Russ
Post Number: 61
Registered: 2-2003
| | Posted on Monday, September 01, 2003 - 10:24 pm: | |
I put generic high performance steel core wires in my 308 GT4 and they do work...but same problem with the stereo. I replaced the capacitor already. Any other ways to fix this? |
Robert W. Garven Jr. (Robertgarven)
Member
Username: Robertgarven
Post Number: 274
Registered: 2-2002
| | Posted on Friday, August 29, 2003 - 1:51 pm: | |
I am running solid core wires on ny gt4 with standard ignition, it works great! Radio has too much interference to listen but I think, the offer better performance over stock. Not for use on newer cars with electronic gadgets! Someone said when you pass a police cruiser their radios are also subject to interference?
Rob |
Mike Procopio (Pupz308)
Member
Username: Pupz308
Post Number: 504
Registered: 10-2002
| | Posted on Friday, August 29, 2003 - 9:38 am: | |
I posted in a previous thread... I'm sure you're looking for many different values to compare. I got 40 to 60 ohms per inch when I tested back in April.
I know other folks have done this though...
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Richelson (Richelson)
Member
Username: Richelson
Post Number: 884
Registered: 12-2001
| | Posted on Friday, August 29, 2003 - 8:43 am: | |
I checked the resistance on the spark plug wires. Here are my values.
#1 1.90K approx. 29 inches
#2 1.83K 27 in.
#3 1.80K 19 in.
#4 1.92K 18 in.
coil was 3.1
I rechecked my readings numerous times but my lengths may be off some but I thought I would provide them for a general idea. I would like to know if these are in spec or do I need new wires. I have heard many different values for wires. Thanks for the assistance.
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