Plasma Ignition | Plasma Jet Ignition

[Aaron Murakami]

Aaron, I take it that Mr Vanagon wanted to delve into the where and how much resistance is appropriate for each circuit; realistically, everyone will have to sort that out for themselves per application I think. While the videos and and your book stress that plasma can't happen with any resistance in the circuit, Vanagon seems to be proving otherwise for his application, which can't be the only one. And I think this is awesome - because if we're saving the air/planet, there should be no hard and fast rules other than "do whatever it takes for you."

And while we're on the topic of wires, I stumbled across a video on youtube that seems to lend credence to leaving resistors in plugs: https://youtu.be/0dFwoJIdNys
Manufacturer's website is http://www.best-itech.com/index.htm where they say that R-type plugs work just fine with their product...something to do with the cable insulation and the connectors/clips on the ends of the cables

"THE" ideal situation is 0 ohms. Any resistances and impedances in a circuit destroy much of the radiant energy.

The diodes go from the coil + connected to the cap + in the msd/cdi units straight to the top of the spark plug. That bypasses the cables so actually you can use stock high resistance cables that might be 5.5k ohms of resistance since the cap in the plug bypasses that and goes straight over the spark on the plug.

However, the advantage with lower or no resistance cables is there will be a much stronger initiating spark created by the hv output of the ignition coil. It is still a CDI/MSD spark and is already stronger than 12v input ignition coil spark, but so much of it gets dissipated by the resistance of the cables. Might as well get what you pay for and go as low of resistance as possible without causing computer interference. On old carb cars, Granatellis are probably best.

The stock plugs are typically around 5.5k ohms as well just like the cables so normally that is around 11k ohms, which is a lot. The secondary in typical black body canister ignition coils are around 10.5k ohms so not sure if that is intentional where they are matching the resistance.

In summary:

1. 0 ohm plugs or close to that as possible are necessary so as not to resist the discharge of the cap across it no matter what kind of situation.

2. Use as low of resistance cables as possible so as not to interfere with on board computers, etc. At minimum, performance cables intended for CDI/MSD ignitions on computer cars is preferrable and on non computer cars, Granatelli is probably best.

[heysoundude]

Aaron, I take it that Mr Vanagon wanted to delve into the where and how much resistance is appropriate for each circuit; realistically, everyone will have to sort that out for themselves per application I think. While the videos and and your book stress that plasma can't happen with any resistance in the circuit, Vanagon seems to be proving otherwise for his application, which can't be the only one. And I think this is awesome - because if we're saving the air/planet, there should be no hard and fast rules other than "do whatever it takes for you."

And while we're on the topic of wires, I stumbled across a video on youtube that seems to lend credence to leaving resistors in plugs: https://youtu.be/0dFwoJIdNys
Manufacturer's website is http://www.best-itech.com/index.htm where they say that R-type plugs work just fine with their product...something to do with the cable insulation and the connectors/clips on the ends of the cables

[Aaron Murakami]

It's bigger than that: you're finding a more reliable, repeatable, stable plasma across engine range with some resistance in the circuit? if so, I'd expect a zero resistance cable like the Granatellis discussed earlier plus a low resistance spark plug should work too, no? Get as much of the ignition energy as fast as possible to where it belongs is the name of the game here, to be able to time the power stroke most efficiently.

Also, @Hellenic Vanagon, does this engine rely on a MAP sensor for fuel delivery?

That is for sure.

Literally, 99% of a typical ignition coil spark energy is lost in the cable and plug resistance.

Granatelli's are great. Worked perfect on my old Datsun.

With the zero ohm cables on my Subaru, the tachometer went screwy and the idle went crazy but not everyone has that problem. With lower resistance wires and non-resistance cables, plasma worked well on the Subaru.

[heysoundude]

The misfiring problem solved by replacing the main high voltage cable, ignition coil to distributor, with a DIY color tv, solid core, copper, cable, (the same applied to connect my plasma with the spark plugs), with the lowest possible, suppressor, limit , for a BOSCH electronic ignition, of 2 kΩ.

So, some, underground, discussions about the superiority of the tv cable vs the various spark plugs cables, (not the carbons which are the worst), seems to be right.

It's bigger than that: you're finding a more reliable, repeatable, stable plasma across engine range with some resistance in the circuit? if so, I'd expect a zero resistance cable like the Granatellis discussed earlier plus a low resistance spark plug should work too, no? Get as much of the ignition energy as fast as possible to where it belongs is the name of the game here, to be able to time the power stroke most efficiently.

Also, @Hellenic Vanagon, does this engine rely on a MAP sensor for fuel delivery?

[heysoundude]

Now I am in position to confirm it: the diodes 6A 1000v are slow and do not permit the plasma discharge above a middle rpm limit.

In a diode chain, you have to consider the cumulative (series) time; individually they are speedy, but clamp time of each diode x number of diodes adds up. it's a lot of energy at the speed of light.

[Hellenic Vanagon]

The first results with the modified NGK are:

#1 2.8% reduction in fuel consumption.
#2 misfiring at high revs.

The misfiring problem solved by replacing the main high voltage cable, ignition coil to distributor, with a DIY color tv, solid core, copper, cable, (the same applied to connect my plasma with the spark plugs), with the lowest possible, suppressor, limit , for a BOSCH electronic ignition, of 2 kΩ.

So, some, underground, discussions about the superiority of the tv cable vs the various spark plugs cables, (not the carbons which are the worst), seems to be right.

[Hellenic Vanagon]

Thank you, Hellenic.
That shows the distributor points input on terminal 2 and all component values are listed except the transformer which appears to be running about 3377Hz based on the resistor and capacitor values on the 555.

Newark.com has a 1,200v 15 amp (110 amp surge) diode rated 20ns for $5.56, and that's the best speed I see anywhere in that range of amps and current with a forward drop a bit on the high side at 4.04 volts. Part number: DSEP15-12CR
The p600 I saw was rated 2.5 microseconds so the DSEP15-12CR is about 125 times faster (2,500ns/20ns=125). An depth search would likely produce some more ideal parameters such as lower forward voltage drop and lower cost.

Richard Gieser

Thank you.

[Hellenic Vanagon]

If your Smart Kit ignition system is not potted in epoxy it would be very nice of you to post component values and any corrections to the circuit that they are showing on their website link, for example, they show the gate of the SCR going to the junction between a cap and resistor instead of the original ignition points.
Details on the transformer is always useful in these ignition circuits since most of the time getting the transformer is more difficult than all the rest of the project.

Thanx.

Richard Gieser

No, no epoxy.

I have these two documents only, (some words in Greek but it is coded in English. For any help please tell me):



(click on the image to enlarge)


(click on the image to enlarge)

Do you want a photo of mine? (A little bit differentiated than that of the brochure, I don't know why).


A question, if someone knows: are there diodes faster than p600, (6A 1000V), in series, but bulletproof as the p600? Thank you.

[Hellenic Vanagon]

Now I am in position to confirm it: the diodes 6A 1000v are slow and do not permit the plasma discharge above a middle rpm limit.

[Hellenic Vanagon]

I'm only guessing that the extra coil hv spark helps to ionize the gap better so that at high rpm, the cap which cannot get full charged to a higher voltage is able to still discharge. Does the high rpm plasma still look just as strong as low rpm or is it smaller?

Where did you get that kit?

#1 The plasma seems that disappears above 3500-4000 rpm.

#2 Smart Kit electronics: https://quasarelectronics.co.uk/Item...ronic-ignition
(But it seems it is not available any more).

[Aaron Murakami]

I am using this, smart kit, unit:



I thought that the problem is due to the low speed diodes.

Anyway, adding a second ignition coil, there is a very substantial improvement in the high revs, letting the plasma to support the low and middle revs operation, as well as, forbidding the fouling of the extra cold spark plugs.

The implementation becomes, progressively, complicated and demanding.

The dialogue with the management of my engine, (a spare mr. Digifant ), continues in a polite mood, (at least for the moment).

I'm only guessing that the extra coil hv spark helps to ionize the gap better so that at high rpm, the cap which cannot get full charged to a higher voltage is able to still discharge. Does the high rpm plasma still look just as strong as low rpm or is it smaller?

Where did you get that kit?

[Hellenic Vanagon]

With MSD or CDI, it is normal to have less plasma at higher rpm. The problem is the cap charger in the units cannot keep up with higher rpm. MSD - can trigger 6-7 times per trigger at lower rpm but as the rpm increases, it may only discharge 1 time per trigger. I don't know for sure this is your issue, but this is very common and expected.

I am using this, smart kit, unit:



I thought that the problem is due to the low speed diodes.

Anyway, adding a second ignition coil, there is a very substantial improvement in the high revs, letting the plasma to support the low and middle revs operation, as well as, forbidding the fouling of the extra cold spark plugs.

The implementation becomes, progressively, complicated and demanding.

The dialogue with the management of my engine, (a spare mr. Digifant ), continues in a polite mood, (at least for the moment).

[Aaron Murakami]

I am leaning to connect in parallel the secondary of two ignition coils, because having a 4.5 mm gap, voltage deficiency is observed in high revolutions.

Their power supply will be independent, the one from the standard ignition and the second from the special module which gives the plasma.

Some tries give a perfect result, simultaneously in high and low revs, but somewhere, in some cases, there is a misfiring under heavy load, although the distributor cap has no signs of arcing. There must be an arcing, somewhere, though...

Two high voltage ignition coils and a plasma unit, feeding the spark plugs, seems as a promising solution. On the other hand, the plasma module gives some signs of overheating struggling to give high current for the plasma and for the second ignition coil.

With MSD or CDI, it is normal to have less plasma at higher rpm. The problem is the cap charger in the units cannot keep up with higher rpm. MSD - can trigger 6-7 times per trigger at lower rpm but as the rpm increases, it may only discharge 1 time per trigger. I don't know for sure this is your issue, but this is very common and expected.

[Hellenic Vanagon]

I am leaning to connect in parallel the secondary of two ignition coils, because having a 4.5 mm gap, voltage deficiency is observed in high revolutions.

Their power supply will be independent, the one from the standard ignition and the second from the special module which gives the plasma.

Some tries give a perfect result, simultaneously in high and low revs, but somewhere, in some cases, there is a misfiring under heavy load, although the distributor cap has no signs of arcing. There must be an arcing, somewhere, though...

Two high voltage ignition coils and a plasma unit, feeding the spark plugs, seems as a promising solution. On the other hand, the plasma module gives some signs of overheating struggling to give high current for the plasma and for the second ignition coil.

[heysoundude]

See if you can get a Samsung S9+ cellphone to try out. They have a 720 fps slow motion camera mode.

Richard Gieser

right, the event happens so quickly, a higher frame rate camera is the only type that can catch it. I have an app on my iphone that does as much as 1000fps, but it eats through memory very quickly at that frame rate.