Plasma Ignition | Plasma Jet Ignition

[Gary Hammond]

Hi RB176,

.................................................. ..... In your experience what brand plugs hold up the best with plasma?

I'm using NGK shunt gap plugs with the plasma ignition in my VW powered Bradley GT. So far, so good. They perform really well in the modified engine. The ignition module is an MSD A6 unit triggered by a hall sensor in the distributor.

[Faraday88]

What was the application for the ignitor? Was it for an oil burner, etc.?

What is your opinion on custom making Coil On Plugs with a HV diode built into the potting compound to seal it all up? How would you go about it?

Hi Aaron,
It was for a Aerospace Project not sure the end application but must be for a spontaneous combustion kind of Fuel im sure like the Petrol.
Yes, Aaron some companies are already making integrated Plug on the Coil. I'm, keen to make a coil to try out what i said for your kind of Plasma Burst,Ido have a few ideas on exactly what you refereed about the HV diode integrated as well.
each layer would be about 10-15 turns and several layers over each other, each layer epoxy insulated. (the old CRT EHT Coil)
I would use several lower Voltage diode is series to the coil (Intermittently) and the encapsulate them as a ready to fire unit!
howz that?
Rgds,
Faraday88.

[Aaron Murakami]

Aaron,
During my tenure at Honeywell I worked for an 'Ignitor' Project, and we custom made these HEI Spark coil, it was a CDI type of Ignition system and we had these miniature coils hand made with heavy insulation using a material (don't recollect the name) like teflon. including the wire jacket made of the same material.
Rgds,
Faraday88.

What was the application for the ignitor? Was it for an oil burner, etc.?

What is your opinion on custom making Coil On Plugs with a HV diode built into the potting compound to seal it all up? How would you go about it?

[Aaron Murakami]

Thanks Aaron, I did a little more reading on the Digital Hp and found another interesting capability of this unit. And that would be that it has 2 power output settings and on low output is 145mj and high is 187mj, still higher than the Street Fire though. In your experience what brand plugs hold up the best with plasma?

That's a great option to have - still a bit hot on the low setting, but really depends on the plugs.

I've used simple off the shelf non-resistor plugs.

What I found that I still haven't had time to test are the iridium and/or paladium non-resistor plugs by WeaponX Performance - something like that. Easy to find online. About $15 per plug or so. They look the most promising but of course will not know unless they're actually tested.

[Faraday88]

Yes, but for $45, that is a better deal for me. It would take well over 10 times that amount worth of my time to do it by hand. I guess it depends on where you are and what economy you're working with.

Aaron,
During my tenure at Honeywell I worked for an 'Ignitor' Project, and we custom made these HEI Spark coil, it was a CDI type of Ignition system and we had these miniature coils hand made with heavy insulation using a material (don't recollect the name) like teflon. including the wire jacket made of the same material.
Rgds,
Faraday88.

[RB176]

Thanks Aaron, I did a little more reading on the Digital Hp and found another interesting capability of this unit. And that would be that it has 2 power output settings and on low output is 145mj and high is 187mj, still higher than the Street Fire though. In your experience what brand plugs hold up the best with plasma?

[Aaron Murakami]

Aaron,
Can'nt we custom build the Ignition coil, the secondary will have to be multi-layered with epoxy insulation.I guess it can be build much smaller also..
Rgds,
Faraday88.

Yes, but for $45, that is a better deal for me. It would take well over 10 times that amount worth of my time to do it by hand. I guess it depends on where you are and what economy you're working with.

[Aaron Murakami]

Hope this works

https://www.amazon.com/gp/product/B0...SIN=B071PBX2XC
$234 for module and all harness, etc. pretty good price.

However, 187mJ per discharge is really strong and would eat your plugs more than twice as fast as the Street Fire if you use it for a plasma ignition system. Keep in mind that even with the smaller 89mJ discharge with the Street Fire that under compression with a lot of air/fuel getting crammed onto the spark, when the cap discharges over the plug, the plasma gets bigger than what you see in open air tests. The air/fuel and mositure in the air feeds the plasma. I think 100mJ per discharge or less is the way to go for regular driving and with good plugs.

For performance where I don't care about how long plugs last, I'd definitely go with that Pertronix unit.

[RB176]

Aaron the picture above is the one I spoke of.

[Faraday88]

Can you post a link to the exact Pertronix CDI you mentioned in your other post?

The Street Fire is about 89 mJ per cap dump - it's around 2uf, which isn't much. After 3000 rpm, there can still be multiple sparks. Low rpm 6-7 per fire and as it goes up, it reduces bit by bit because the cap charging circuit can only charge up so fast.

The speed that the cap charger won't change the plasma - just a plasma will happen whenever the cap does discharge. If it is once per trigger, then you get one plasma burst per trigger. If it is 6 per trigger, then you get 6 plasma bursts per trigger.

3 ohms isn't much but I would recommend a coil intended for capacitive discharge systems. I like the Pertronix one because it is fairly low cost for a performance ignition with really low resistance in both the primary and secondary. 0.32 ohms primary - https://www.amazon.com/gp/product/B0...SIN=B002Q363XM only $45 delivered on Amazon prime. MSD has coils with much lower resistance if you can imagine that but they're a few hundred but not necessary.

Aaron,
Can'nt we custom build the Ignition coil, the secondary will have to be multi-layered with epoxy insulation.I guess it can be build much smaller also..
Rgds,
Faraday88.

[RB176]

Hope this works

[Aaron Murakami]

Ok thanks I can pick up a MSD Street Fire for $149. I read the specs it says multi fire spark to 3000 RPMs after that single fire. Does that affect plasma spark at all? I’m not sure of the microfarads it puts out I’m sure it would be adequate. Also my coil has a 3.0 ohm internal primary resistor do you think this will be a problem or will I be able to use it.

Can you post a link to the exact Pertronix CDI you mentioned in your other post?

The Street Fire is about 89 mJ per cap dump - it's around 2uf, which isn't much. After 3000 rpm, there can still be multiple sparks. Low rpm 6-7 per fire and as it goes up, it reduces bit by bit because the cap charging circuit can only charge up so fast.

The speed that the cap charger won't change the plasma - just a plasma will happen whenever the cap does discharge. If it is once per trigger, then you get one plasma burst per trigger. If it is 6 per trigger, then you get 6 plasma bursts per trigger.

3 ohms isn't much but I would recommend a coil intended for capacitive discharge systems. I like the Pertronix one because it is fairly low cost for a performance ignition with really low resistance in both the primary and secondary. 0.32 ohms primary - https://www.amazon.com/gp/product/B0...SIN=B002Q363XM only $45 delivered on Amazon prime. MSD has coils with much lower resistance if you can imagine that but they're a few hundred but not necessary.

[RB176]

I just came across a CDI box from Pertronix that has multi spark all the way to redline. Maybe a better choice?

[RB176]

Ok thanks I can pick up a MSD Street Fire for $149. I read the specs it says multi fire spark to 3000 RPMs after that single fire. Does that affect plasma spark at all? I’m not sure of the microfarads it puts out I’m sure it would be adequate. Also my coil has a 3.0 ohm internal primary resistor do you think this will be a problem or will I be able to use it.

[Gary Hammond]

Hi RB176,

Question if I use a crank trigger ignition with sensor to create a Hall effect with a coil and diode will this still create Plasma spark without a MSD box? The MSD would be just for multiple sparks correct?

NO !! That is not correct!!

You need a capacitor discharge circuit attached to the coil to make this work. The MSD is a multiple spark (capacitor) discharge circuit that discharges it's capacitor several times each firing event. A single cap discharge is all that's required to get a single plasma event at the spark plug. But the MSD is good because it gives multiple plasma events every time it fires.

The coil and diode can't work their magic without a cap discharge involved.


PS -- Sorry Aaron, I didn't see your response before I posted this.