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2G Dynatek ARC-2 Install Help

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LidnDom

Proven Member
34
0
Jan 13, 2014
Tampa, Florida
I have a 95 Eclipse with a 6-bolt swapped 90s CAS. I'm also using Buschur's COP.
There are 3 wires that I don't know where they go to


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After installing the Dynatek ARC-2 the car started up fine. However, my tachometer stopped functioning properly. The tach will read an idle of around 100-200 when ECMlink shows 900-1000. I have my settings on the Dynatek as follows: Restrike, Rising Edge, Crank
I also have the black box plugged in
 
If I were you I'd ditch the power transistor and wire it in directly, then use the tach signal from the dynatech and not from the ptu.

They kinda suck though. They take a shot often and generally don't help anything. Get a good set of plug wires and make sure the coil pack is well grounded.
 
After installing the Dynatek ARC-2 the car started up fine. However, my tachometer stopped functioning properly. The tach will read an idle of around 100-200 when ECMlink shows 900-1000. I have my settings on the Dynatek as follows: Restrike, Rising Edge, Crank
I also have the black box plugged in

Your settings are correct. If your tach isn't working, my suspicion is that the black box may be bad, or the install harness is off. The black box is the tach adapter for the ARC-2, and it creates the signal that goes back to the PTU, so the PTU will then generate the tach signal. Did you have a good tach signal with the stock coils prior to installing the ARC-2 and COP? If the tach reading was bad before, then it could be a case of a bad PTU.

You could wire the white wire in to the tach to make it work, but I'd suggest getting the tach adapter checked/replaced if it is the problem.

Do you have a stock coil pack you can try in place of the COP?

If I were you I'd ditch the power transistor and wire it in directly, then use the tach signal from the dynatech and not from the ptu.

This is a bad idea. The PTU gives it a good 0-12V input signal with a big voltage swing. Removing that and going directly to the ECU will make the ignition more noise sensitive, and likely to create a misfire where there wasn't one before.

They kinda suck though. They take a shot often and generally don't help anything. Get a good set of plug wires and make sure the coil pack is well grounded.

Do you even know how the ignition works? Judging by your comments, I'm going to guess not.
 
Your settings are correct. If your tach isn't working, my suspicion is that the black box may be bad, or the install harness is off. The black box is the tach adapter for the ARC-2, and it creates the signal that goes back to the PTU, so the PTU will then generate the tach signal. Did you have a good tach signal with the stock coils prior to installing the ARC-2 and COP? If the tach reading was bad before, then it could be a case of a bad PTU.

You could wire the white wire in to the tach to make it work, but I'd suggest getting the tach adapter checked/replaced if it is the problem.

Do you have a stock coil pack you can try in place of the COP?

I had the tachometer working with the COP alone without the Dynatek. Are there any methods for testing the tach adapter? What white wire are you reffering to?
Thank you all for your replies!
 
Sorry, green wire not white wire. It's been a long time since I developed that ignition for Dynatek, on my 95. We did a green wire for the tach signal because that was the color we always used. Now I think tach = white wire because that is the color code I deal with making ignitions now, I left Dyna a long time ago.

The best test method for the adapter really is to swap it out. I know someone else on here recently had a tach adapter issue. Dynatek replaced it and that fixed the issue. They are pretty good taking care of customer issues.

As for the 3 wires, one is the green tach output. The other 2 are (I think) a clutch switch input for the launch limit, and a timing retard enable wire.
 
Your settings are correct. If your tach isn't working, my suspicion is that the black box may be bad, or the install harness is off. The black box is the tach adapter for the ARC-2, and it creates the signal that goes back to the PTU, so the PTU will then generate the tach signal. Did you have a good tach signal with the stock coils prior to installing the ARC-2 and COP? If the tach reading was bad before, then it could be a case of a bad PTU.

You could wire the white wire in to the tach to make it work, but I'd suggest getting the tach adapter checked/replaced if it is the problem.

Do you have a stock coil pack you can try in place of the COP?



This is a bad idea. The PTU gives it a good 0-12V input signal with a big voltage swing. Removing that and going directly to the ECU will make the ignition more noise sensitive, and likely to create a misfire where there wasn't one before.



Do you even know how the ignition works? Judging by your comments, I'm going to guess not.
. Excuse me, but what? So, Triggering the dynatech trough the ptu and a tach adaptor is less noise prone than triggering it directly? So what testing have you done on this? What isolation could the ptu possibly provide? It sounds like you are the one that doesn't understand how our ignition systems work. I don't know how my reccomendations are anything less than correct. As for the dynatech not being helpful, it provides a slight gain in spark energy, but the spark duration is very short. It provides a rapid voltage rise across the plug which is good to prevent fouling, but it does little to ignite a very dense charge. If cdi was so good why would blown alchohol engines use a magneto?
 
. Excuse me, but what? So, Triggering the dynatech trough the ptu and a tach adaptor is less noise prone than triggering it directly? So what testing have you done on this? What isolation could the ptu possibly provide? It sounds like you are the one that doesn't understand how our ignition systems work.

I understand fully how they work. What is your degree in again? Do you understand what the function of a transistor is? Do you know what the T in PTU stands for? Tell me, if the ARC-2 triggers at 4+V, is a 0-5V low current signal going to be more noise immune, or will a 0-12V signal with 10x the current? What happens if the ground bounces up around a volt or so in both cases?

And to answer your other question, yes I have done testing with noise immunity on the ARC-2 inputs when it was being designed. And I've also seen a few issues in them in the field. Do you know when the issues occured? When some knowitall didn't listen about the voltage swing.

Don't let the facts get in the way of your rebuttal. You always seem to have enough arrogance in your replies to make up for any lack of knowledge.

I don't know how my reccomendations are anything less than correct. As for the dynatech not being helpful, it provides a slight gain in spark energy, but the spark duration is very short. It provides a rapid voltage rise across the plug which is good to prevent fouling, but it does little to ignite a very dense charge.

The problem is that you don't know how your facts are less than correct, because you ignore any facts that don't come from someone as condescending as you. And no one like that exists.

The CDI also provides voltage to bridge gaps where the stock ignition will fail. This is basic knowledge. Anybody who has ever tested with a CDI will point out the CDI will light a larger gap off that a stock ignition can't. You might not have been able to do that, but it is probably because you were focusing on something ridiculous like grounding the coil.

You can't even spell the name of the company right. Dynatech makes exhausts. Dynatek is the company that makes the CDI.


If cdi was so good why would blown alchohol engines use a magneto?

We went over this before, apparently when I pointed out your incorrect facts, it didn't sink in the first time. Many blown alcohol engines use CDI now. Magnetos were a tried and true technology, that many people stick with for simplicity. It isn't the only ignition used though.
 
Ok you were on the payroll at dynatech? So if triggering directly off the ecu outputs is such a problem how does mitsubishi get away with it it? Probably low input impedance in the ptu. If you have enough rfi to pull a 4v signal to ground, you have much bigger problems, or the input impedance of the dynatech is way to high and that's a design flaw. What is the input impedance of one anyway?

The tach adaptor is a hack. Running a dummy coil just to make the connections easier.

In my experience the dynatech sucks. It needs tighter gaps than stock to run on my car. That's with brand new Taylor 409 wires and brand new ngk br8es.

And id like you to point out a pro team that is winning with a cdi over a magneto. I've never seen anyone choose a cdi over a promag, unless they couldn't afford it. Hell in our local superstock alcohol pull tractor class they outlawed magnetos to keep the power down.

I'd like to know what testing you've done. I'd like to see some data from a high boost alcohol motor cdi vs magneto vs battery and coil. Cylinder pressure data and heat release rate. I'll look for some sae papers tomorow.
 
Ok you were on the payroll at dynatech?

No, I never worked at Dynatech. I have worked for a few companies that make exhausts, but never them.

So if triggering directly off the ecu outputs is such a problem how does mitsubishi get away with it it? Probably low input impedance in the ptu.

Not really low impedance. They are an inductive ignition where they can filter it out. And if they accidentally switch the coils on for a microsecond, it doesn't matter. But they also don't trigger at 4V, they switch on at lower because they were made to switch just above ground, and if there is a little delay of a low pass filter, that is designed into the system and maps. The CDI has to use this signal not as an amplifier, but as a trigger. So it is just trying to figure out when the signal is real to trigger the CDI output. The more you work to filter out noise, the more delay you are going to have.

If you have enough rfi to pull a 4v signal to ground, you have much bigger problems, or the input impedance of the dynatech is way to high and that's a design flaw.

The problem isn't the 4V drop to ground, but the 1V drop from 5V down to 4V. If you are coming down from 12V to 4V, that is 8V. 8V is larger than 1V.

It's not a design flaw. It is that you aren't using it the way it was designed. An improper install is not a design flaw.


The tach adaptor is a hack. Running a dummy coil just to make the connections easier.

It is also to fool potential diagnostics on other vehicles. Just because it doesn't serve a purpose on your hacked up car doesn't make it a hack. I think for most people an ignition that can be dropped in in a few minutes and provide a big gain in energy is far from a hack.

In my experience the dynatech sucks. It needs tighter gaps than stock to run on my car. That's with brand new Taylor 409 wires and brand new ngk br8es.

Then you were doing something really wrong. It could be that your box was defective, but based on your lack of understanding, I'd bet it was some screwed up user error. The box puts out 180+mj, WAY more than the stock setup. And that stock setup drops with RPM, while the ARC-2 has good energy way past redline. And the coil output voltage on the ARC-2 should be a good bit higher too.


And id like you to point out a pro team that is winning with a cdi over a magneto. I've never seen anyone choose a cdi over a promag, unless they couldn't afford it. Hell in our local superstock alcohol pull tractor class they outlawed magnetos to keep the power down.

Oh, so now they have to be winning? And if I show you one that wins races, then it'd have to be one that won a championship? Or it'd be a class that doesn't count? You are a knob.

I don't follow drag racing much anymore. I know 1 team right now. They run CDI in NHRA Pro Mod, and they are winning races. The last time I discussed it with them, CDI is not uncommon at all.

I'd like to know what testing you've done. I'd like to see some data from a high boost alcohol motor cdi vs magneto vs battery and coil. Cylinder pressure data and heat release rate. I'll look for some sae papers tomorow.

Testing? I measured out what the stock ignition does on several DSMs, it is limited. Good for a stock system, but not nearly as good as a CDI. The CDI provides much more energy and voltage. I think the customers who put one on and immediately were able to open up the gap, crank the boost up, are all the evidence needed.

The specs for the Dynatek ARC-2 are on their datasheets. If you want me to provide more test data, I can do that. We'd just need to arrange an acceptable form of test, and you'd need to be willing to pay for it up front.
 
I appreciate all your replies. I have another question about moving the Dynatek ARC-2 into the cabin. Is it as simple as splicing the connector going into the ARC-2 module and soldering 18 ga wire to extend it? I don't want it to mess with the functionality of the Dynatek Arc-2
 
If you have enough rfi to pull a 4v signal to ground, you have much bigger problems, or the input impedance of the dynatech is way to high and that's a design flaw. What is the input impedance of one anyway?

Not really low impedance. They are an inductive ignition where they can filter it out. And if they accidentally switch the coils on for a microsecond, it doesn't matter. But they also don't trigger at 4V, they switch on at lower because they were made to switch just above ground, and if there is a little delay of a low pass filter, that is designed into the system and maps. The CDI has to use this signal not as an amplifier, but as a trigger. So it is just trying to figure out when the signal is real to trigger the CDI output. The more you work to filter out noise, the more delay you are going to have.

Maybe what will help people understand the difference in the noise issues, is that the CDI is charging a capacitor prior to firing. In order to get the 100-200mJ, it charges a 1-1.5uF capacitor to 400-550V. To do this, it rapidly switches a current of anywhere from 20-50 Amps peak, at a frequency of 10 KHz to 100KHz(depending on brands of CDI). The grounds inside the CDI can bounce up as a result of this high current, and the ground quality from the box to the battery.

The stock system uses the PTU to charge the coils, storing the energy in the coils. It may charge as much as 6 Amps at idle, but at higher RPMs, it is only charging them to 4-5A, slowly building current over a period of a few milliseconds. That may seem fast, but relative to the CDI, the charge builds very slowly.

That isn't a design flaw, as much as it is fundamental electronics. More current through a wire will result in higher voltage drop across it. Throw in 20 year old ground wires, corrosion, paint, improper install, and you can have an issue. But calling it a design flaw is demonstrating how little you know about the subject. That would be like calling it a design flaw that the blown alcohol motors don't run properly when you put 91 octane in them.

And speaking of the blown alcohol motors, whether they are all magneto as you claim, or not as I pointed out, it really is a moot point. We aren't running a factory magneto in these cars, it is a simple transistorized inductive ignition. There are pros and cons to both inductive and CDI in these cars, but it has very little to do with what ignition blown alcohol motors are running.
 
I appreciate all your replies. I have another question about moving the Dynatek ARC-2 into the cabin. Is it as simple as splicing the connector going into the ARC-2 module and soldering 18 ga wire to extend it? I don't want it to mess with the functionality of the Dynatek Arc-2

I would suggest not doing that. In the development of it, we ran it underhood in my car and others in plenty of heat. I know after I left they kept working little tweak to improve how it worked at higher temps. Just in case the heat is your concern.

My big concern with extending wires, is where you are running them. The CDI coil output wires have 500+V pulses that could affect the signals on other wires around it if you put it in a bundle with the existing vehicle wiring.

Aside from that, the wires that go from the stock ignition to trigger the ARC-2 can probably still be 18 gauge. I'd consider moving the coil output wires up a gauge if you lengthen them
 
Im a member there but the M&W is what is popular on that forum so I was directed to DSM forum for dynatek
 
Thanks a lot. Need to buy me wire ends and make an adapter harness now. Need to search this furum for nitrous control using aem.
Thanks again
 
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