TheSamba.com :: View topic - Resistor vs. non-resistor plugs

Fri Jan 20, 2012 1:40 pm

Hey everyone, i'm in the market for some new plugs and have been doing tons of research. I have been looking into the NGK B5HS non resistor but am concerned that this plug will cause the stereo to whine etc.

" being that it's a none resistor plug it cause's to arc in to other electrical components,example:using a none resistor plug in an everyday car/truck etc will cause a whine in your stereo;the whine will increase,and decrease at different rpm's"

Any input?

Fri Jan 20, 2012 1:44 pm

i've never had a problem with non-resistor plugs. the resistor is for protecting the various onboard computers in a modern car. the resistor reduces spark energy, so you don't need or want the resistor in a beetle with carbs and points.

Fri Jan 20, 2012 2:40 pm

kyleader wrote: Hey everyone, i'm in the market for some new plugs and have been doing tons of research. I have been looking into the NGK B5HS non resistor but am concerned that this plug will cause the stereo to whine etc.

" being that it's a none resistor plug it cause's to arc in to other electrical components,example:using a none resistor plug in an everyday car/truck etc will cause a whine in your stereo;the whine will increase,and decrease at different rpm's"

Any input?

That is the exact NGK plug that I am using in my bugs with stock Bosch plug wires with no problem. Granted I just have a stock radio so I am not sure regarding your reference to stereo. Both of my cars are generator equipped.

Fri Jan 20, 2012 10:41 pm

My 74 sb has a kenwood and inlike other cars it does not whine on none resistor plugs , i wonder if its because the engine is in the ear ,.. :shock:

Sat Jan 21, 2012 4:12 am

I'm pretty sure resistor plugs were created only deal with interference to AM radio. If you don't listen to AM, it should be a non-issue.

Whine is usually associated with the alternator or generator and can usually be cured with some filtering. Most modern car electronics are OK with some ripple, on the 12V supply though.

Dave

Sat Jan 21, 2012 6:19 am

Resistor plugs are used to reduce noise in the radio and interference in sensitive electronics. As the VW has no sensitive electronics they are for noise suppression. Since your stock plug wires are made of strands of wire {0 ohms resistance}, unlike modern cars that have carbon wires {Varies my manufacturer, 40 - 50 ohms per foot 150 - 1,200 ohms per foot}. One would think you need resistor plugs to reduce rfi in the radio but the engineers at VW were on the ball. They built the resistor into the bakelite end that attaches to your plug. By doing this all plug wires have the same resistance {modern cars vary with the length of the wire}. This ensures an equal spark on all wires with the relatively weak coil output {roughly 14 thousand volts 14kv}.Modern cars are running 45 to 60kv some may be higher, so resistor plugs with high resistance wires is not an issue.

Running a very high output coil with solid wires will create a higher magnetic field around the wire being fired. When this field collapses, the energy can induce a voltage into adjacent plug wires causing a crossfire situation. If it induces into a compuer or other electronic wire it can fry the component.

Adding resistor plugs to a wire that already has a built in resistance will weaken the spark. In some cases causing a misfire.

Short story, use non resistor plugs.

Sat Jan 21, 2012 7:38 am

Why would you want to run non resistor plugs? What would be the advantage? I haven't heard of anyone running them since the 50's

Sat Jan 21, 2012 9:32 am

Have you measured the resistance through the distributor rotor? This is where VW added the resistance in the High Voltage circuit to reduce RFI.

In race cars where performance is "King" you will see non-stock distributors w/ zero resistance rotors or the resistors drilled out of the rotors:
http://www.huelsmann.us/bugman/RotorTech.html
This gets the max voltage to the spark plugs to produce the hottest spark that can jump the widest gap.

Tue Jul 30, 2013 7:40 am

does it matter if you use non resistor plugs on a resistor rotor or vice versa?