You are hilarious Brad, stop being a smart ***! :-)

 

Small bit taken from the service manual...

 

And even smaller schem. of the system

 

Thanks for spoiling my chance at getting that bet :P

Brad

 

YES! I get to win the special olympics!

The system is described very clearly on pages 16-32 and 16-33. The system is a twin fire, and fires both plugs on one coil at the same time. You were right about that.

Where you were wrong: On page 16-33 there is a diagram showing how the system is actually layed out. Both the spark plugs and the coils connect to ground, as per my earlier suggestions. Current only flows one way through the coils.

I'll take that $1,000 bucks now

What you were probably thinking of is something GM did, where odd cycles fired across a plug in one direction, and even cycles fired across the other way. To make that work GM had to have the plug screw into a plasic (insulated) socket in the cylinder head and then the current went both directions and never touching the ground. To do that they needed one coil per plug with two capacitors per coil. It was a pretty wonky capacitive discharge set-up.

BTW: I'll take that $1,000 bucks now

 

No results when searching for your name and ground or idle. Just doing a search on idle(without specifying posts from you)did find one thread that I read about 5 posts from before I had my hourly BS quota filled. They were talking about smoothing out the signal to the sensors. Which would be a neat trick to do when the grounds you add don't even connect to the sensors. The sensors are grounded with their own setup, direct wires to the ECU for the most part. I didn't see your post in it though. Maybe you can find the link to the thread you were talking about?

Brad

 

You mean you will give that $1000 now? You STILL don't get it, do you? The coil secondary is floating. The diagram shows the 2 plugs connected to ground(which is really just a shorthand, but they are flowing from one plug to the other, they aren't flowing to the battery ground. The secondary of the coil doesn't tie in to ground, and without that, it is <b>impossible</b> to create a loop of current flow to ground. They would have had to center tap the coil and ground it to get the setup you are describing, which would decrease the amount of available spark energy for the firing cylinder. The ground you see on the coil is part of the transistor circuit I described earlier, it does not go to the coil secondary. I left my copy of the Evo manual at work unfortunately. But I already know I'm right, 7 years doing ignition design gives me a little edge over you If you doubt me, go out and test it on your car. I don't think you want to know you are wrong though

Brad
PS IM me for my paypal address. I think I driving to Vegas with my winnings. I will post pics for you though

 

here's the diagram...

If you look at it you can see that all 4 plugs, both coils, and the battery are shown to connect to ground...

Pretty spiffy shorthand, huh?
BTW: I'll take my $1,000 bucks now!

 

Here is a link showing a little more about coils. Its a handbook written for Toyota, but they still use the same laws of physics as Mitsu, so the pics apply. Page 10 is the page you should look at:

http://www.autoshop101.com/forms/h23.pdf

It shows current flow on a DUAL output coil. If you look at the preceding pages, you can see how SINGLE output coils work. Notice how all of them are drawn with a ground on the secondary side of the coil. Notice that the DUAL output coil doesn't have this? Then notice that the EVO DUAL output coil doesn't have this either.

Brad
PS Hurry up with the paypal, I am making reservations for my trip as I type this.

 

Cool. Now get out your crayons(the red one preferably), and circle where the coil secondary(the half of the coil that is connected to the plugs) is grounded to create that current loop.

Thanks,
Brad

 

Sigh - I've never said the high voltage side was directly grounded; just grounded through the plugs.

The high voltage side completes it's circuit by having the low voltage side run current through the coil to store up a net positive charge for the high voltage side and then discharges that through the spark plugs.

I did read your link, and the systems there are different than the one shown for the Evo. The biggest single difference with the diagram you referenced on page 10 of your link is that there is a diode shown on one side of the coil, preventing current from flowing down one plug wire. The result is that current could be made to travel up the that wire.

The Evo diagram doesn't show a diode of that nature, thus current will flow down both plug wires at the same time when the coil is triggered.

The diagrams you referenced for the earlier systems also use different circuits from that of the Evo.

BTW: I want my $1,000 bucks....

 

A net positive charge for the positive side? Haha, you don't even know what you are talking about. The primary creates a magnetic field. When the magnetic field breaks down, that creates a voltage in the secondary. If there is a path for current to flow(a loop) on the output of the secondary, current will flow. If not, a large voltage develops on the secondary, and no current flows.

What you are describing is almost vaguely how a capacitor in a CDI works, but you are missing a million things for it to be correct.

The secondary IS NOT physically connected to the primary, and no amount of wishing on your part will make the primary be the way that the loop is completed.

If as you describe it, the diode simply blocked the current from flowing down, then it would NOT make it flow back UP. There has to be a potential difference across the wires to make it flow back UP that wire. Potential difference is sometimes referred to as voltage by people in the know. Flowing back UP the plug wire is done because of the nature of the coil design. The coils on page 10 function the same as the Evo coil. The current flows down one plug wire, and up the other. Since you can't even get the basic concept of how current requires a loop to flow, I will NOT try to explain the function of the diode, it would be like trying to teach a chimp calculus.

You don't even understand the difference in them, they are not as different as you realize. They just wont plug in exactly the same, you'd need to put new plugs on them, and possibly change the dwell time(I won't explain this basic concept). The transistorized ignition is used in both designs, the difference is the location of the transistor.

Now why on earth would I give you $1000 when you are wrong? Apparently no amount of reading is enough to teach you, how about a little experiment? I will show you how I set up test benches at work without a ground to the engine block.

Remove one of the coils on your car, pull the plugs out of the head, or better yet, get two new plugs, and leave your old ones in the head. Then plug the two plugs back into the plug wires. Get a clip lead to attach the two ground electrodes together(without this, the loop that I am telling you about will not be complete). Make sure they do NOT touch ground anywhere, since according to you, they need to touch ground to create a spark. Once its setup, it should be exactly the same as if the plug were in the head, but the head wasn't grounded. Now start the car, and watch the sparks jump the gap. How can they do that if they aren't grounded to the head? Either I am a magician that can work magic over the internet, or they don't need to be grounded because they flow in a loop through the coil, take your pick. Once you are done, IM me to make payment arrangements.


Brad

 

According to the diagrams I saw on the sight you're referencing that would work for a Toyota, but not for an Evo. If you want to try that with the plugs and coils from your Evo go ahead. In fact film it and prove me wrong.

If you used the coils from the Toyota it would work fine and validate your point (at least to yourself). Didn't you say all our ignition systems are the same?

Your stale BS, personal attacks and derission have gotten old, and I'm tired of your techno-spew with twisted facts. I'm also tired of your taking what I say, restating it as your "expert knowledge", then adding some jargon to it and calling me wrong.

Time for me to quit letting you waste my time.

 

Upset that your lack of knowledge is being called out? I guess I can understand that.

Claiming that the toyota coils are somehow wired differently than the Evo coils to avoid paying up? I can't say that I'm surprised. You probably have to do things like that alot, otherwise your ignorance would get pretty expensive huh? I'm sure you noticed that according to the Toyota wiring diagrams both of the spark plugs were grounded as well, but oddly that didnt make the current flow back to the battery like you claim.

So you are saying that if I hook an Evo coil up on a test bench, and prove you wrong, you will pay me $1000? Or will you back pedal out of it?

The other people who were disagreeing about this figured out VERY quickly that what I was saying was right. They seem to understand how ignitions work, and just missed a minor point about the coil topology on this car, which is easy to do. Why do you have that much more difficulty agreeing with it?

People wonder why ground wires are so popular, and think that it must be because they work, but in truth it is because people like you don't understand why they don't work. And a little bit of knowledge is a dangerous thing, it leads you to come up with all sorts of wrong info.

But just state in a post, that you WILL pay up if I prove you wrong, and all will be good

Brad

 

Some random thoughts that come to mind, in no particular order of importance:

Brad is correct in this thread. He is probably the only one here that _fully_ understands the ignition system on a EVO (he designs and builds ignition systems for a living :-)

Grounding wires are magic beans and make no power.

Every sensor on the motor has it's own ground back to the ECU.

The drivetrain is grounded only for the starter and for EM noise.

Message boards are mental masturbation.

Mike W