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Discussion Starter · #1 ·
I'm trying to run stock Gen 3 ignition with a megasquirt MS3X ECU. It's going OK but I've fried a coil and trying to work out the best dwell settings, which means researching exactly how the stock systems work.

Does anybody already know if the stock Gen 2 ignitor is smart or dumb, meaning does the ignitor control the coil dwell time or does the ECU control it?
And also does anybody know if the Gen 3 ignitor is smart or dumb?

The reason I'm suspecting there may be a difference is because Gen 3 ECU setups won't work with a Gen 2 igniter, and from the power FC threads I've read on the forum it looks like the Gen 3 Apexi dwell settings add more crank degrees of dwell at higher RPMs implying the ECU is controlling dwell, but I read that to convert Apexi FC for Gen2 igniters you can simply put 30 in every RPM box, does this work because the Gen 2 igniter is smart and controls the dwell internally?
Unfortunately in old Apexi FC threads many of the screenshots no longer work (photobucket)

If any knowledgeable people can chip in it'd be appreciated

Thanks
Dan
 

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Discussion Starter · #4 · (Edited)
The 3SGTE uses an external ignition module. In 2nd Gen 3SGTEs, this module is responsible for controlling the charging time of the ignition coil. These are called "smart modules" since they control coil dwell.

Source: Alternate engine management for the 3SGTE
Great find, very interesting post thanks.

So sounds like the first part of my theory is true the gen2 igniter is smart.
Just need to find out now if the gen3 went to being dumb and dwell control moved to the ECU!
 

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Great find, very interesting post thanks.

So sounds like the first part of my theory is true the gen2 igniter is dumb.
Just need to find out now if the gen3 went to being dumb and dwell control moved to the ECU!
ScarecrowX, whom I quoted, said the 2nd gen uses a smart external igniter, because it controls dwell.
 

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I’m running a MSPNP on my gen3 without any dwell advance so would think yours would be same. Maybe you have the wrong values in yours which is why igniters have failed?

jim
 

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Discussion Starter · #8 ·
I’m running a MSPNP on my gen3 without any dwell advance so would think yours would be same. Maybe you have the wrong values in yours which is why igniters have failed?

jim
Yes its the dwell duration and cranking dwell settings I am trying to work out. As mine isn't a PNP I don't have any base settings.
What dwell time and cranking dwell (milliseconds) works for your gen3?

Thanks
Dan
 

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Sorry just a typo was supposed to say smart.
Right on! Just making sure.

Generically, most dwell settings I've seen are between 1 to 4 ms.
I have a gen 2 igniter, stock distributor and stock coil with AEM and my dwell table is 1.8 ms from idle to 4000 rpm, then decreases in an exponential curve to 1ms at 7000 rpm. That is how it was setup on the startup map and I've had no reason to change it.
 
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