Can anyone explain the difference between suppressor and resistor spark plugs? I was told many years ago resistor spark plugs reduced radio interference I remember when I put an am radio on the Farmall super m that you could hear a crackle each time a plug fired. I'm betting racing plugs don't have resistor or surpressor.
i'd bet they are one and the same. They, resistors, were marketed as the zero radio interference plug vs. the old copper core wires (Packard by name). If you had the Packards you didn't need a radio. "Radio suppression" plugs hit later. When the "rag" core wires came about, they both all but went away.
Yes, probably the same, the resistor is used to suppress radio interference. I did read about how they work a while ago, but I have been unable to find it again. The ignition gives off a high voltage peak first, before the spark lights, then it immediately drops down to a fraction of the original voltage as the spark jumps the gap and current starts flowing. You may go from 10-20-30 000V to something more like 2000V in basically no time at all. The thing is you have some capacitance in the high voltage circuit, a very small amount but it does what capacitors do - it gets charged up, and then release that charge. Here you go from having it charged to tens of thousands volts, to something that by comparison is more like a short circuit, the charge built up gets discharged FAST, and a fast discharge of a huge voltage means a very high current for a very short time. Adding some resistance in the plugs, wires etc. slows that discharge down considerably, and limits the peak current. This reduces the radio interference (which doesn't only affect radios, but may disrupt or even destroy other electronics - electronic ignition systems included). The added resistance has little impact on the spark strength, as the normal current flow is rather low, a few thousand ohms doesn't do much to it. I wish I could find the document about this again.
The non-resistor type plugs are known to deliver a more powerful spark rather than the resistor type. The resistor type is actually resisting some of that spark energy. This is also the reason why those racing plugs are non-resistor types. Hello, In our quest to get a more powerful spark for out 671 supercharged 292 c.i. SBC motor, we used Lodge “pink” non resistor plugs for the best results. Currently, there are a ton of spark plug that are non resistor types. There is even a cap that provides a non resistor style connection. Check the plugs out to see which one would work for you. At first, we used the normal Champion Spark Plugs for our 283 SBC street/drags motor. Then when we went to a 292 c.i. size with all blower spec parts, we used Pink Lodge Plugs. Although we did not have a radio in the Willys Coupe, we were told that the non resistor plugs gave out more spark energy. (Mailliard word of wisdom) So, we bought two sets. One for the preliminary fire up to check everything prior to lining up for a run down the dragstrip. During the wait time, we installed the same (second set) Lodge Plugs for the actual run. We pushed the Willys Coupe into the class lanes and started only when the front gate was opened and we headed up to the starting line. Jnaki The results were pretty good for a first time build. But, the valuable information from Joe Reath and Joe Mailliard, gave us a base with which to work our build and performance information. The Lodge plugs were a little more in cost, but well worth it. Later on in our desert motorcycle racing time period, we still used a different Lodge Spark Plug for our custom dual spark plug head. Why dual spark plugs? The switch on the handlebars allowed me to switch from one Pink Lodge Plug to the other. Out in most of the desert races, despite the best air filtration unit, some dust or something always jammed up the main Lodge Spark Plug. So, a quick switch of the faltering motor gave instant life back into the motor using the new (second) spark plug. By the time we got another 40-50 miles of dusty trails, the plugs jammed again from the dust and dirt, so one more flick of the switch and the old plug had cleaned itself and now was ready to battle again. This went on for 100 miles of the usual Hare and Hound races in dusty desert environments. We did pass up other racers with one plug and those guys/girls had to stop to change the original single plug. We learned that dual spark head modification from our first encounter of having to stop in the hot, dusty trails to change the fouled single plug days or races. Not the best thing when it is boiling hot and dusty. YRMV
There's a lot of variables here...sometimes a resistor plugs or wires will cause an issue, somtimes not...
I switched to resistor plugs back in the 70's and never looked back. 383 Dodge "pony car" with..... MINIMAL I repeat MINIMAL space to get a wrench on the plugs! Plugs lasted only a few month(or was it weeks??!) then knuckle busting time. Resistor plugs lasted a LOT longer between plug changes. For a street ride I couldn't tell any loss of power. 6sally6
Resistance filters out amperage and amperage is heat,think welder when you weld a heavy piece of metal you crank up the amps. A system that uses a coil of .6 oems would be a high amperage system. Remember coil output is dependent on coil input.
Many aftermarket EI have .6 ohm coils use dwell control to limit current,especially at low speeds..I believe the orignal GM HEI does not have dwell control..so it's said many replacement coils suffer an internal short and fry the module...
Years ago, non resistor plugs or wires played hell with AM radios and TV's. Now that nobody hardly listens to AM radio anymore and everybody has either cable or satellite TV, it's doubtful many folks would know you were running them. I don't know if it would effect digital over the air TV reception, but it kinda doubtful.
SOURCE - https://www.vdlfuelsystems.com/anything-and-everything-you-want-to-know-about-spark-plugs/ If you notice, they began to appear at the same time period as electronic IGN was introduced. They became even more important with an ECM/PCM.
I think with all the talk radio on AM these days that listenership is up pretty high. People love their talk radio. Besides, FM sucks these days. AT least around So Cal it does. The largest listening audience in the country, and the worst FM choices in the country. I hardly listen to FM at all any more.
My wife’s Corvair has a working stock AM radio but the interference when the engine is running makes it mostly unusable. It has suppression plug wires and a condenser on the coil. I converted it to an alternator, but there’s no condenser on the regulator. Would resistor spark plugs help? When I installed the new engine, I bought a few sets of NOS AC Delco spark plugs off of eBay because our auto parts store couldn’t get them at the time. I’m wondering if there is a substitute resistor plug I should try.
I have no clue about a corvair motor, but one trick used by the ancients was to change the coil wire to the distributor to a supression type wire. It was not a total cure but helped a lot. That and a new set of quality supression plugs/wires might do it.
We have as many or more talk FM stations as we do AM around here. AM is mostly religious stations or Mexican music. Still a few good FM rock stations and some country if you're into that.
Is AM really still a thing over there? Sure, there are still some AM stations here, but I haven't listened to any in decades. I assume they're still there, I haven't checked, any time I switch to AM it's just to hear if there's any lightning in the area.
In the 70s we sold Hays electronic conversion kits. One of their systems was called S4,this was a high anpage system that used a .6 oem coil. Besides having enough fire to burn a wet dog the timing retarded as the RPMs increased,grate for auto trans. drag and circle track cars.We had a test bench that we could run the systems and check for problems. At the yearly winter car show we would have a booth and show off our wares. Using the test bench with the S-4 system running at about 1300 dist. rpms I would put on a fire power demonstration. Using a solid coil wire with a clip on the end holding a piece solder I would solder two pieces of brass shim stock together.
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