Plasma Ignition | Plasma Jet Ignition

[Aaron Murakami]

Hi Ron,



I think you're right!

I did a little searching with google and see that your ignition system would be a real bear to modify. It has a fixed distributor and timing is controlled by the engine control module (computer). The trigger pickup is magnetic - appears to be a switched reluctance device with two rotating pieces. One piece is a finger and the other is a notched wheel. The two work together some way to give the trigger signal to the computer and then on to the "igniter". The "igniter" is a solid state device that amplifies the computer signal and switches the coil. And the coil is built into the distributor.

In order to use the MSD box and an external coil, the built in coil would have to be bypassed and electrically totally removed from the circuit. Then since the "igniter" is designed to drive the coil with a lot of current, it probably would be difficult to adapt it to only trigger the MSD box. I also found that a weak or failing "igniter" can cause the symptoms you described even with the stock ignition system.

Gary, did you see my post?

Ron has the white trigger wire which is for mechanical points and the red small wire, which is for the ignition switch positive to turn on the MSD going to the distributor instead of the violet/green wires. There is no way it can ever work correctly like that.

Igniters aren't the problem - I did it in my Subaru and it has an igniter and I did it with the wasted spark ignition on top of that, which some thought was impossible until I did it. Of course the way I invented to make it work on a wasted spark ignition coil pack system with isolated secondaries with opposite polarities on each end is a bit elaborate but is the solution.

In any case, I think the correct trigger wires on the msd has to be used and the small red wire needs to be on the + switch on the ignition or manual toggle switch to the + of the battery and it should work fine. Even if it doesn't wind up working, it has to be wired up correctly to begin with in order to assess what the deal is.

[Gary Hammond]

Hi Ron,

I have come to the conclusion that this cannot be done on my 1996 Toyota Tacoma pickup!
If ANYTHING is attached to the top of the plug, like needs to be for the HV to be transferred, it goes wacky and crossfires and misfires to the point it will not run!
For some odd reason the way the distributor electronics work on this particular vehicle it just will not let it be modified to run plasma, period!!

I think you're right!

I did a little searching with google and see that your ignition system would be a real bear to modify. It has a fixed distributor and timing is controlled by the engine control module (computer). The trigger pickup is magnetic - appears to be a switched reluctance device with two rotating pieces. One piece is a finger and the other is a notched wheel. The two work together some way to give the trigger signal to the computer and then on to the "igniter". The "igniter" is a solid state device that amplifies the computer signal and switches the coil. And the coil is built into the distributor.

In order to use the MSD box and an external coil, the built in coil would have to be bypassed and electrically totally removed from the circuit. Then since the "igniter" is designed to drive the coil with a lot of current, it probably would be difficult to adapt it to only trigger the MSD box. I also found that a weak or failing "igniter" can cause the symptoms you described even with the stock ignition system.

[Aaron Murakami]

Hi Aaron,
If you are talking to me I have the Street Fire #5520
Coil I have is Nology ProFire
I am using orange and black to the coil, white and small red to the old internal distributor coil wires
I can't seem to find the info for what kind of pickup this distributor uses so I don't know?

Thanks,
Ron

The orange and black to the ignition coil is correct.

The small red wire from the MSD should be going to your ignition switch, which connects it to the 12v battery + when the key is turned on. It should not be going to your distributor.

Violet and Green with the little plug are for the magnetic pickup for most electronic ignitions.

White is for mechanical points.

You have a 96 - I'd be very surprised if you actually have points. If not, there should be 2 wires coming from the distributor for magnetic pickup. Most likely they are red and green. Red goes to the violet wire and green goes to the green wire. If they are different colors, it shouldn't matter because the magnetic pickup just shorts those wires like a reed switch closing. If at least one wire matches green or violet, then at least connect the like color.

You said you have the little red and white going to the distributor - that definitely sounds incorrect to me.

If you have points, you'd probably only have 1 wire coming from the distributor that simply connects the white wire in the msd to ground and that is how that is triggered.

Those goofy symptoms you're experiencing with your ignition can absolutely be caused by using the wrong trigger. I can't guarantee that is the problem, but I think you have it wired wrong.

I emailed Nology to ask what polarity the HV output is. Most people don't care but this is the more rare case where knowing the polarity is absolutely essential.

I saw your email about non-compatibility with your truck - I don't buy it for a second. Check the above trigger and small red to a switch and it should work fine.

[rokan]

I have come to the conclusion that this cannot be done on my 1996 Toyota Tacoma pickup!
If ANYTHING is attached to the top of the plug, like needs to be for the HV to be transferred, it goes wacky and crossfires and misfires to the point it will not run!
For some odd reason the way the distributor electronics work on this particular vehicle it just will not let it be modified to run plasma, period!!

[Richard]

I'm guessing it would be I would double check directly with MSD though because I'm not familiar with that truck or engine. If the ignition coils has a simple + and - primary input with a single HV output that goes to a distributor cap, then it should work fine but please don't take my word for it.

Here is the instruction/data sheet for the street fire module with about half a dozen or more hookup situations. You can probably find your exact one in there and if so, should work fine. They're all pretty standard back then. https://www.jegs.com/InstallationIns...1/121-5520.pdf

Thank you, Aaron.

Richard Gieser

[Aaron Murakami]

Hi Aaron, is the MSD 5520 ($144.42 on Amazon) good for my '73 Dodge pickup with the 440 engine and factory electronic ignition which uses a magnetic pickup?
I'm using the Pertronics 0.3 ohm Flamethrower coil.
Thanks.

Richard Gieser

I'm guessing it would be I would double check directly with MSD though because I'm not familiar with that truck or engine. If the ignition coils has a simple + and - primary input with a single HV output that goes to a distributor cap, then it should work fine but please don't take my word for it.

Here is the instruction/data sheet for the street fire module with about half a dozen or more hookup situations. You can probably find your exact one in there and if so, should work fine. They're all pretty standard back then. https://www.jegs.com/InstallationIns...1/121-5520.pdf

[rokan]

Not points and condenser
Not sure if it is inductive or hall?
Do you have an easy way to determine which it is?

[rokan]

I'm going to draw everything out just so there is no question about anything.

What is the part # for your MSD?
What is the part # for your Ignition Coil make/model?

What wire are you using to trigger the MSD? Which color(s)?

Hi Aaron,
If you are talking to me I have the Street Fire #5520
Coil I have is Nology ProFire
I am using orange and black to the coil, white and small red to the old internal distributor coil wires
I can't seem to find the info for what kind of pickup this distributor uses so I don't know?

Thanks,
Ron

[Richard]

I'm going to draw everything out just so there is no question about anything.

What is the part # for your MSD?
What is the part # for your Ignition Coil make/model?

What wire are you using to trigger the MSD? Which color(s)?

Hi Aaron, is the MSD 5520 ($144.42 on Amazon) good for my '73 Dodge pickup with the 440 engine and factory electronic ignition which uses a magnetic pickup?
I'm using the Pertronics 0.3 ohm Flamethrower coil.
Thanks.

Richard Gieser

[Aaron Murakami]

I'm going to draw everything out just so there is no question about anything.

What is the part # for your MSD?
What is the part # for your Ignition Coil make/model?

What wire are you using to trigger the MSD? Which color(s)?

[heysoundude]

I'm sorry, @rokan. I'm wrong and the experts are arriving with ideas and input to resolve your difficulties and teach me a few things.
(Not really sorry: mission accomplished. This place is a bit too quiet at times, and a cry from the wilderness can go unheard from what I've seen, until some action starts on a topic.)

[Gary Hammond]

Hi Rokan,

What triggers your ignition system? Points and condenser? Inductive pickup? Hall effect pickup?

[rokan]

I have checked and re-checked my junction and it isn't shorting there. If it was it would only be the one wire/cylinder shorting and would still run on 3 cylinders but all 4 cylinders start misfiring at the same time even though I have only installed one of my modified wires to test with?
Those are my thoughts exactly, that some RFI is disrupting the signal for all of the cylinders. This exact problem occurred before I installed the HV coil or the MSD unit. Originally I put copper rods down inside the plug boots to make contact with the connector that clips to the top of the plug to get a direct connection to my plugs without any resistance and the problem was the same even with all the stock equipment, as soon as I connected a wire to my plug rod it would start mis-firing on all 4 cylinders.

[rokan]

It isn't mis-firing thru my electrical connection, I have checked and re-checked that. It isn't a plug shorting out as I described earlier because that would mean just one cylinder isn't firing. AGAIN, when I do the test with only 1 of my modified wires connected to #1 cylinder the whole engine mis-fires when I connect one end of my diode jumper wire to my spliced connection and it isn't touching anything!!?? Again, open on the other end, nothing connected to it, no direct electrical connection to anything, it is a wire that is ONLY connected at the plug wire junction I made and nothing at the other end.

[rokan]

Connecting all diodes together at the end that goes to the coil + and each diode going individually to their own plug is definitely correct. The only diode that will be used like that will be whatever plug fires, the the rest of the cap discharges through that diode over the gap.

If the distributor cap arcing is a problem, it's feasible but would be the first time I've heard of anyone encountering that problem.

The previous owner of the Datsun I have changed the distributor's points/rotor systems to an electronic ignition so I never had the opportunity to have that problem if that is what is even happening. That is one option possible is that if that is a problem, you could replace the distributor with an electronic ignition. Then you just use the magnetic pickup input for the MSD.

As far as your hookup goes, it's correct. Each diode to the wire spiced into the ignition cables should be just fine.

Although you tested the diodes in both directions and get a spark in one direction but not the other, I would still do the definitive test with the ignition coil HV output to see the polarity with the pencil test.

I read and re-read the pencil test and still something isn't clear to me how to perform that test?