[POOH23312566]

Hey new to the forum, I have a IGN1A coil from amp efi and I couldn't find any dwell time table for my dwell compensation and was wondering you guys have one laying around. Thanks!

[PSIG]

Welcome! This is a mash of compiled info from multiple sources. Use at your own risk, and I suggest testing before use. While they may appear reasonable, I have not run these numbers. Good luck!

IGN1A (Mercury 2442 5278, AEM 30-2853, etc)

Base dwell 12V: 3.0ms
Discharge (spark burn time): 2.9ms ±10%
Max dwell duty cycle: 40%
Max continuous dwell: 9ms
Output (no load): 40kV minimum
Output (50pF load): 40kV ±10%
Output Energy: 103 mJ ±7%
Peak Secondary Current: 102 mA ±10%
Turns Ratio 71:1
Maximum Current: 19 Amps
Maximum Battery Voltage: 17 Volts

Approximate voltage corrections (12.0V @ 100%):

8V = 164%
10V = 118%
12V = 100%
14V = 77%
16V = 66%
18V = 61%

I have seen a higher dwell with similar voltage compensation, e.g., 3.6ms. Do your thing.

[POOH23312566]

Thank you man, you're a lifesaver. I'll test it soon as soon as I get off to work. Btw, what should I set my cranking dwell time? Should I put 3.5 ms?

[PSIG]

If using fixed cranking dwell, I'll crank the engine to check stable cranking voltage after cranking begins (check log), then follow the dwell voltage correction for that voltage. Then I add a little more for if the battery is low. If that is unknown, many will set fixed cranking dwell for the lowest the ECM will function (typically 8V). Depending on the coil, that setting should be safe as the voltage is lower - so the current is lower. That's the point of voltage corrections. Your call, and do your thing.

Be sure to follow the Wiki or TS notes for Dwell Protection settings , so your cranking dwell can actually work, e.g., 5ms cranking + 3 ms = 8ms minimum dwell protection. Increasing that would not hurt anything

Side comment - ECMs should follow voltage corrections at all times, including cranking. Then it's always the right dwell for any voltage condition, cranking or otherwise.

[jack stones]

Thanks for the detailed explanation! I'll definitely check my cranking voltage and adjust accordingly, just to be safe.