Spaceball 1

iTrader: (8)

Like i said in my first post in this thread. I was not having miss fire issues like other people, but i knew about the problem. Most people just go straight COPs GTVEVO and I are just trying to show that there is another choice before going to the COPs. I didn't even think that i was having a miss fire, but with these new settings the car pulls harder and sounds a bit different. It also doesn't seem to foul the plugs when idleing any more. I haven't even tried to open the gap back up on the plugs yet.

srt4-Joe

iTrader: (1)

So who would like to help me out? Although I do not run an AEM on an Evo, but a Srt.

The coil on our vehicle is 2 coils molded into one. So they're is still two coils that fire to to cylinders. It is not a wasted setup.

They're are 36 teeth on the tone ring.

1 tooth = 10 degrees.
2000rpm = 12 teeth /ms
6000rpm = 36 teeth /ms

Any idea on how to setup this to get a good dwell for the coil?

GTVEVO

iTrader: (22)

FYI after reading on AEMPower I noticed that they are stating that the coil type used sources all of the power from the ECU and it can cause the ECU ignition drivers to get too hot with too much dwell so I would keep this in check when doing any testing. I would hate for someone to damage something due to not properly testing. Looks like AEM is at least giving you a reason that they may not be able to drive the coils very hard. I have still left the results of what I see below.

Once again from what I can tell another very very low setting on the 1510 base cal file. Please be aware that I don't know allot about the technical factors on the SRT-4 but if the data you provided is correct I see that the Max Dwell is once again set very low at 12.5% dwell just like the EVO was. The other tables don't look too bad but I would say because of the Max Dwell your charge time is being capped through the entire rpm range since the Dwell vs RPM table is static @ 200. My recommendation would be to move you max Dwell to atleast 9 from 4.5 and test there. This should double your charge time and only setting the charge for 25%. Even then this is very very low but it should give you something to test and you should see atleast some sort of improvement. If you do I would say move the Max Dwell up to 50% by changing from 4.5 to 18 and do more testing and logging. Remember too much dwell will fry the coils but in most cases operating at 50-65% should be safe to my knowledge.

With all of these changes be aware you are still going to be capped due to the static Dwell vs RPM table set at 200. Basically your table settings are trying to dwell quite a bit or around 6.7 ms at 12 volts but because of your Max Dwell being set at 12.5% I am fairly certain you are being cut off in the mid and high rpm range drastically.

If you do test please let us know how it goes.

srt4-Joe

iTrader: (1)

Do you mind explaining how you got this though. I'm super stumped and am eager to learn this. When you talk about "teeth" on the Evo are you speaking of the tone ring or cam gears or what?

If they're are 36 teeth...

50% would be 18 teeth? Correct?


So if I set the Max teeth at 18 do I not need to adjust the Dwell Factor? It's set at 30 from AEM because they do not recommend anything over 35 as it tends to fry coils. What exactly does this number do? The max teeth kind of overrides this does it not?

GTVEVO

iTrader: (22)

Yes, you are correct 18 teeth would be 50% of 36 total teeth per cycle (2 revs since no wasted spark is used).

If AEM is saying this people must be frying them even at lower rpm to make that worry valid. If you raise the Max Dwell you will be allowing the Dwell to hold a higher charge all of the time so this would be the same result as in toasted coils. If you change the dwell factor I don't see your actual dwell being changed due to the Max Dwell at this point. Right now from a glance I don't think you are probably ever getting the dwell set in the tables due to the Max Dwell setting being so low but I would have to calc every rpm out to be sure of that.

Over on AEM board they make it seem that the ignition driver in the AEM box could get to hot, did I just miss understand that? Have you don't any testing with the coils and or dwell settings? Sounds like there might be some hardware compatibility issues in your case honestly but I am still not for sure.

srt4-Joe

iTrader: (1)

No you read it right. BUT it's the physical coil that people have to replace when this happens. The ignition driver is where? The ECU?

So basically because everyone keeps frying they're stuff I really do not need to raise the dwell any higher huh.....whata hunka junk

GTVEVO

iTrader: (22)

Ya they are making it sound like the driver is inside the ECU but if that were the case I would think the ECU would get the damage unless the drive malfunctions after too much heat causing the coil to fry. They aren't being very clear here.

It sounds like more testing really needs to be done on the hardware as to why they AEM Driver is overheating the coils so easily. Their has to be a difference somewhere with the power that is getting to the coil between the two ECU's because they don't just magically overheat something is making them and why. I wished I could be more help but seems like the only advice I can give you is logic and theory at this time.

Spaceball 1

iTrader: (8)

I found a little info on why the dodge coils are over heating the coil driver in the EMS

Because Chrysler uses direct-drive coils, the ECU has to source all of the current. It is completely normal for the ignition drivers to get warm, but with too much coil dwell, they will get too hot. This becomes a problem if the engine stays at high engine speeds for an extended period.

srt4-Joe

iTrader: (1)

Well the ECU sends a voltage to the ASD fuse in the fuse box, then the ASD routes the signal to the coil... I'm stumped, I would like to double what I have no but i'm afraid doubling the Dwell will realllyyyy screw things up.

awdboosted

iTrader: (30)

I had foul plug issue with my dsm because I was running a copper plugs and 9's a CDI help a little. I don't know if I would blame that on the Dwell settings thou. Being too rich can cause that too.

srt4-Joe

iTrader: (1)

Well I found out the culprit. Seems as though the AEM itself is frying; supposedly the pin outputs on the EMS cannot handle the extra heat. Does this mean the only solution is an external ignition driver like the AEM twin-fire?

GTVEVO

iTrader: (22)

I don't think the AEM Twin-fire will even help your issue or help very much, the only reason I say this is because I had tested the Twin-fire and Sun ignition amplifier on the EVO and both only made minimal differences before I started seeing misfire again. This test I did was with a friend on two different EVO's. We both ended up moving to the DSM coils which worked better than anything by far. If it was me I would try to move over to a straight up CDI box if possible. As it would handle the entire charge and only be looking for a signal from the ECU.

BBrooks

You're right the AEM ecu can only handle 1.5amps max before it burns the solder trace on the ignition circuit. The SRT is setup without an ignitor as far as i know, so it's counting on the ecu to handle the load capacity of the coil.

(cheap fix)
I'd try using a 1g-2g dsm ignitor(7amp max) or one of the ones Groc mentioned above.

srt4-Joe

iTrader: (1)

Sweet, i'm going to be looking into a CDI then or this DSM ignitor. Thanks for the solution, I understand the problem now.

bradrs

The neon coils are VERY good. And they actually will charge a bit quicker than the DSM coils. You could get a really strong spark with them, if you got a strong enough ignitor. Even with the DSM ignitor and around 5.5-6mS of dwell(should be a safe match) you should get a nice strong spark.

If the AEM can only handle 1.5A before burning a trace, then I would never use it to direct drive a coil.

As for why the Sun ignition amp didn't make a difference, figure out what it is doing. A quick calculation will tell you why it doesn't work.