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Plasma ignitions, Krupa firestorm plugs...

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Anyone ever tried these experiments out? the krupa spark plugs can be built at home with an old plug, but do they HAVE to have a plasma ignition system to work worth while?

http://peswiki.com/index.php/Directory:Firestorm_Spark_Plug

The plasma ignition is slightly more complex to build on your own, but if you're an electrician than it shouldn't be too hard..

there are a few company's claiming to make them like aquapulsar and eurobahn but they're for cars, i was wondering if it's possible to build one for a dirt bike?

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Looking at that, I see one thing that goes against what I know of good plug design, and that's the big ball ended electrode. The reason precious metal spark plugs work better than other standard types is that the use of iridium, platinum, and the like allows the use of a much smaller gauge electrode. The advantage to this is that it is much easier for a spark to jump from a finer point than a large, rounder one, and low spark voltages and/or long rise times are less apt to result in a short over the insulator via anything deposited there.

It seems to me, given that, that this plug would absolutely require a very high energy secondary output to function very well.

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I don't know about the point being a better conductor.. just because they make spark plugs using a point, and precious metals, then isn't it logical that the only reason they use a point is so they don't have to 'waste' all their precious iridium? they could use less in each plug and save themselves $$$$.

The thing that always gets me, is that Tesla ALWAYS used domes and orbs because they are the best conductors of electricity. He stood behind the fact that a fine point is actually the worst shape to conduct as well.

The firestorm plugs are said to never misfire due to the dome/cage design because when one area becomes ionized, which would usually cause a misfire on a standard plug, the spark logically just switches to a different spot along the cage.

I kinda just want to build one of his plugs for the fact that they will never wear out, that's his claim at least. And my reasoning is that they will be more resistant to fouling as well if installed into one of my grimy 2ts:smirk:

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Hmmm,

In my experience a spark always jumps from the one electrode to another at the point that requires the lowest voltage to jump. Smallest gap, sharpest point, Etc. I see no way to make a giant ball of electrical flame in the combustion chamber with only a spark plug change. Physics don’t change. A dual electrode plug doesn’t provide two sparks. The spark simply jumps to one electrode until it erodes to the point that it is easier to jump to the other electrode so I’m not sure what the big ball trick is supposed to be. I'm always a little suspicious of these type things. I mean if this was really available and could improve emissions and mileage that much I think the OEMs would be all over it. Could you imagine their sales on a full size truck with a v-8 that would get 40MPG with almost no emissions? I would buy one today and so would everyone I know. How about a 60 mpg compact. Sounds pretty attractive. Another issue I see is that the plug protrudes way too far into the combustion chamber. I don’t think you could get that into many engines without piston interference. Especially all the 12.5:1 four stroke stuff out there today. Anyway, just one guys take on things.

Thanks

MSD Mike

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I don't know about the point being a better conductor.. just because they make spark plugs using a point, and precious metals, then isn't it logical that the only reason they use a point is so they don't have to 'waste' all their precious iridium? they could use less in each plug and save themselves $$$$.

The thing that always gets me, is that Tesla ALWAYS used domes and orbs because they are the best conductors of electricity. He stood behind the fact that a fine point is actually the worst shape to conduct as well.

The firestorm plugs are said to never misfire due to the dome/cage design because when one area becomes ionized, which would usually cause a misfire on a standard plug, the spark logically just switches to a different spot along the cage.

I kinda just want to build one of his plugs for the fact that they will never wear out, that's his claim at least. And my reasoning is that they will be more resistant to fouling as well if installed into one of my grimy 2ts:smirk:

To start with, the matter of the fine wire being an inferior conductor to a larger one, or the ball being a superior conductor, is a misplaced concern on one count, and inaccurate on the other. In electricity, resistance offers resistance to current, not voltage. Since there is very little current involved, the comparative resistance levels of a very small iridium electrode and a larger steel one is not a factor; neither offers significant resistance when compared with the wire size in the secondary coil winding.

As for the ball, think of it as a series circuit. The ball can't suddenly conduct more electricity than is allowed to reach it by the much higher resistances upstream. And besides, when you are dealing with a spark gap, "conductivity" is not the issue, unless you are talking about the conductivity of the air in the gap.

It is a fact that a spark will jump more easily from a sharper or finer point than from a larger, blunt, or ball shape. Electricity is not often thought of in this way, but it is actually solid material (electrons being handed from one molecule to another) in motion, and it has a certain degree of kinetic inertia. It's very analogous to water in a pipe in several ways. When the spark occurs, a stream of electrons under high pressure (voltage) rushes toward the plug gap. In one scenario, this stream is funneled into an ever smaller conductor terminating in a point where a small number of molecules are being passed the electrons of a much larger number lined up behind them. The pressure is immediately too great to resist, and the spark crosses the gap.

In the second scenario, the charge arrives at the end of the plug to find a big, conductive mass with all kinds of places to hand off electrons to, and like water flowing into a wide spot in a stream, the current slows down, and the pressure drops off, creating a temporary delay in the rise of voltage immediately at the end of the electrode. Under conditions where there is a semi-conductive path available other than the plug gap, like fuel on the insulator, the spark current may find it easier to turn the corner and flow across that alternate, rather than fly off the end and cross the gap. With a normal ignition, such a plug will be far more prone to fouling than a fine wire electrode. It's not a matter of conserving the metals, it's one of deliberately choosing to make the electrode finer. The use of precious metals allows a fine electrode to be used without combustion gases eroding it quickly.

That's a bit simplistic, but that's in essence how it works.

As far as the "ball of flame" phenomena, that will never happen with a single spark. The spark will, as Mike said, just find the easiest way across every time until it wears out one path and moves to another. The Tesla style fireball requires a spark that is continuous over at least a short period so that the ionization you mentioned can take place. One of the MSD ignitions can probably fill that role to some degree. As I recall, they fire continuously for something like 20 degrees of rotation after the timed ignition point.

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That was an excellent explanation for the masses. A spark ALWAYS initiates from the sharpest edge. And that point changes. Every spark that jumps causes erosion from that point, on an atomic level. On a wide, 2.6mm regular electrode, it will move all around the circumference of the electrode. A fine wire of precious metal by it's smaller dimensions keeps the spark in a consistent location, and is more durable against the erosion.

Check the condition of old sparkplugs in a car when changing them. They will have eroded into a blunt dome.

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Excuse my miswording, conductivity wasnt what i meant. this is the quote i am referring to:

"The central electrode has been changed from a cylindrical post to a hemispherical dome,surrounded by four arched electrodes, each of which being positioned at a constant distancefrom the hemisphere. Nikola Tesla was using “orbs” on spark gaps over a hundred years ago.He found that orbs hold the highest amount of charge.(sharp points holding the least)." ~Robert Krupa

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Check the condition of old sparkplugs in a car when changing them. They will have eroded into a blunt dome.

Exactly! that's how he came up with the design in the first place actually, he noticed that they always wore down to a stub in the shape of a dome and he decided to skip the wear process and just design them in that shape.

"During this time, I went through a 55-gallon drum full of grimy used spark plugs. I inspected them all very carefully and found that the older the model of spark plug was, the more the centre electrode of the plug was worn all around the side. It took the shape of a small ball. It was a half a ball—a dome shape, to be exact.

"That's when I thought, 'If that's what the spark plug wants to be, then why not start off with that shape and see what it does?' So, I took a brand new plug and filed it down into the shape of a dome and fired it and noticed it worked a little bit better. But I still had a problem with the grounding side. Next, I whacked the ground off and started putting different configurations of grounding electrodes on it, and I held everything together with toothpicks to make it easier to change.

"When I put a half a loop on the grounding side, it seemed to fire a little better. Then I took the head of a screw and bashed it with a hammer until it took a dome shape. Then I took the other side and dimpled it, creating a concave—an inverted dome, really. I carefully balanced that battered dome on top of the electrode of the new plug that I had filed to accommodate it, and then I put a half a ring over it for the negative electrode, again holding all that together with toothpicks. And when it started firing, the amount of energy coming off the plug was just crazy, and I said to myself, 'I've really got something here!'" ~also, Robert Krupa

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One of the MSD ignitions can probably fill that role to some degree. As I recall, they fire continuously for something like 20 degrees of rotation after the timed ignition point.

Your right about spark jumping more easily from a sharp point. Fine wire plugs are often used in high boost automotive applications due to lower break down voltages. They will often work when a normal size electrode will not.

Increased spark energy can only come from the ignition amplifier and coil, not a spark plug. We can make huge ignition power but it’s not practical for dirt bike applications due to the required size of the electronics and coils. Even the 44 amp magnetos we use on top fuel application do not make the "ball of fire" shown. They will make you a ball of goo if you get hit by one though :smirk: Ask me how I know.

Seriously though, there are methods using capacitors in spark plug wires or our spark plug caps that can make a spark plug look something like that (Even a regular plug) However, they are not delivering more energy, they simply take the energy available and deliver it over a much shorter period of time. It makes a great visual if used with a powerful ignition but it still doesn’t change available energy. It just delivers it over a different (Shorter) time frame.

I won’t name names but I have seen other wiz bang plugs and plug wire devices that show the ball of flame effect. They often use one of our MSD boxes in conjunction with one of the capacitor type devices to drive the "ball of flame side" of their display.

There are a lot of tricks out there.

Thanks

MSD Mike

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"That's when I thought, 'If that's what the spark plug wants to be,

Not to be smart but if I pulled a worn out piston or bearing from a trash can I dont think that my first thought would be. That what a piston wants to be.

Mike

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... his point was that a spark plug naturallly wears down to a dome, so why not just create a dome in the first place because what could it possibly wear down to? a smaller dome?

although that was humorous, ill give ya that much! hahaha

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Do you guys remember this thread about spark energy?

http://www.thumpertalk.com/forum/showthread.php?t=936997

Once the air/fuel mixture ignites, does it matter if it was ignited by a sharp point or a ball? Does more fuel burn because a spark of greater energy started the combustion?

I might be totally wrong here, but it seems to me that either you have combustion or you don't. Once combustion starts, won't it cause a chain reaction that grows at a rate dependent on fuel mixture rather than the spark that started it? As we all know, fuel combustion in the cylinder takes a significant amount of time, that's why we have spark advance. Why would the fuel decide to burn faster or more completely if it was started by a spark plug of a different geometry? I can see the advantage of having two or more spark plugs that start two or more flame fronts on opposites sides of a cylinder, but this is one plug that starts one flame front from the same place as all other plugs.

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I understand, I just couldn’t resist. A point I will make though is that if you take a worn out domed shaped spark plug and a new spark plug with equal air gaps the new one with sharp edges will always require lower firing voltage. We have tested it many times and the result is always the same.

Thanks

MSD Mike

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Nikola Tesla was using “orbs” on spark gaps over a hundred years ago.He found that orbs hold the highest amount of charge.(sharp points holding the least)."
Precisely. Is the goal of a plug to hold a charge? Or would you rather have the charge jump the gap?

Once the air/fuel mixture ignites, does it matter if it was ignited by a sharp point or a ball? Does more fuel burn because a spark of greater energy started the combustion?

No, and no, as you are aware. The advantage to a system that produces spark of extended duration is that it works better under conditions where igniton may possibly not occur within the 50-80 microseconds a CDI spark lasts. An example would be at times when the mixture density was very low, and/or intake vacuum high, such as at a light cruise with a very lean running low emission engine. Misfiring can occur simply because there wasn't a gasoline molecule close enough to the plug when it sparked. A longer lasting spark gives it more opportunity to find one and ignite it.

Under normal circumstances, it doesn't matter. Once it's fired, it's fired. But a sharp electrode is more apt to fire than not.

Mike, I loved the piston comment...:smirk: Perfect.

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Kind of an interesting note on Spark energy and a bit of MSD history. When MSD started in the early 70's a couple of engineers from White Sands Missile Range actually were working on an ultra lean burn carburetor to improve fuel economy. They were having issues with the stock ignition systems of the day lighting the super lean fuel mixtures the carburetor created. To combat this they designed a multi sparking CD ignition. It lit the fuel mixture nicely. We never sold a carburetor but we have sold an awful lot of multi spark ignitions over the years.

Sorry to get sidetracked.

Mike

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Under normal circumstances, it doesn't matter. Once it's fired, it's fired. But a sharp electrode is more apt to fire than not.

.

Something to ponder. :smirk:

If you were challenged with lighting a fire and burning as much wood as possible in 10 minutes and your 2 options were

1) Use a match

2) Use a blowtorch

Which one would ignite the wood faster, more thoroughly and more effectively? Then ask yourself, given the timeframe I had to burn that wood, did it matter which device I used to trigger the event?

BTW +1 a sharp electrode always takes less voltage to fire off properly. Hence why we have fine wire spark plugs. This also means that spark duration can go up as well in certain circumstances.

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on the topic of fine-wire plugs and the such, since it takes less voltage to create spark would they spark earlier than a standard plug? like is it slightly advanced relative to a regular nickel-plated one? I ask because right along with all this plasma ignition research ive been doing, i also stumbled upon those "pulse plugs" that have a capacitor built in, so theoretically it takes time for that capacitor to fill, and then release all at once (similar i suppose to the firestorm plugs on a standard ignition would, because of the orb shape?)

im just thinking aloud here, because even the pulse plugs, which ARE available btw claim to improve fuel economy because you can run a leaner mixture without throttle hesitation. very interesting indeed, i do wonder if that will cause higher operating temps though and possible seizure?

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also, does the ability to release energy in 1 quick powerful burst, rather than over a longer duration with less intensity, increase the speed of the flamefront? if that were the case, then i could see the more "complete burn" claim starting to hold water a little bit..

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also, does the ability to release energy in 1 quick powerful burst, rather than over a longer duration with less intensity, increase the speed of the flamefront? if that were the case, then i could see the more "complete burn" claim starting to hold water a little bit..
The speed of the flame front is almost completely determined by fuel chemistry, heat, and pressure, and not by spark intensity at all, beyond the point where ignition of the first fuel molecule occurs. msiddalingaiah earlier mentioned the use of multiple plugs. When fired simultaneously, or nearly so, as in the old CZ singles, this speeds up the flame by the simple expedient of lighting it in two places.

Take the wood/blow torch analogy offered earlier. Since wood is relatively difficult to ignite and doesn't sustain combustion until a large volume of it is under combustion, and since one would be free to move the torch around the fuel supply, it makes a poor comparison to a volume of fuel that has to be ignited instantly from a single fixed point.

A closer analogy would be a 6 inch circle covered with match heads. You're going to light this from any one place you like by touching another match to any one match head in the circle. That one will ignite the 5 around it and the flame will spread out at a rate determined only by the chemistry of the match heads. The overall time that combustion takes will be influence only slightly by using a bigger hotter match to light the first match head, and probably not at all by how long you hold the match in the middle of the pile after the fire starts.

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also, does the ability to release energy in 1 quick powerful burst, rather than over a longer duration with less intensity, increase the speed of the flamefront? if that were the case, then i could see the more "complete burn" claim starting to hold water a little bit..

On many aftermarket plugs / wires and the such with capacitors in series with the output of an ignition coil I'm a sceptic for many reasons but I'm not going to rip into the whys when they aren't here to ask.

To answer your question on output it's a hard call. I can say this. In a no cost venue such as F1 half the engines use CDI and the other half use inductive ignitions which is what you are describing. CDI is high voltage, minimal on time, Inductive is low voltage long spark time. The coin is still up in the air over which type is superior.

All OEMs(automakers) use inductive because it will provide a spark burn time for up to 30 degrees of crankshaft rotation where CDI is about 2 degrees. This is the primary reason most CDI's have multispark, but multispark is limited to about 3000rpm on most CDI's due to repeated charge / discharge cycles required and the time required to charge them. The reason OEMs went to Inductive is to make sure each combustion event occurs due to CAFE and emission guidelines as the inductive style ignitions are more likely to cause combustion in the chamber then the CDI is. What this does at elevated hp levels is still up in the air. Many racers claim CDI is best and many racers claim Inductive is best.

In our testing elevated burn time has always netted more power in high powered forced induction setups BUT I believe that it is all in the setup, which components are used and how they are used together. Putting together a complete system that works harmoniously is a rather large part of the equation.

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