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Anyone have experience with the MSD 6M-2 Marine Ignition Control Box - tech notes attached

C

contender31

Regular Contributor
Any idea how this system would benefit me on my 2 1990 454 Crusader 350 hp engines? I have standard factory prestolite distributors with after market Pertronix ignition conversion kits.

This is the technical explanation - The tech told me that about 25% of fuel is not burned on each stroke thus the 25 % raw fuel is being discharged out the exhaust.

Tech notes:
The heart of the MSD Marine Ignition System is the MSD 6M-2 Ignition Control. The MSD 6M-2 is a capacitive discharge ignition that provides the spark plugs with high energy, multiple sparks. This multi-sparking feature ensures that the air/fuel mixture inside the combustion chamber is ignited entirely to prevent loading up of the plugs while idling out of the "no wake" zone. In addition to the multi-spark feature, the MSD 6M-2's hot capacitive discharge spark occurs for a full 20° of crankshaft rotation to improve power throughout the entire RPM range.
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Thanks
 
25% unburned fuel is very unlikely. THere is an advantage in wider spark plug gaps, but I would tend to think that the most benefit is with lean running engines, with more difficult to ignite fuel/air charges. Wider gaps require more voltage/energy, as does higher compression ratios. That's not the mode your crusader is operating. Most boat engines are not running on the lean edge and are not running hi-compression ratios. Certainly not yours and mine.
Saying that, I'm running the Jacobs Omni-pak system, and i'm therefore able to remove altogether the ig. coil. But, don't expect a 25% increase in range, that is a fantasy.
 
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I leaned out my carb system from stock. I have no misses. Understand that a stock system won't "miss" either, unless there is a cylinder in trouble (oil fouling). I had run a 440 V-8 with plug hard deposits from an unknown cause. The Jacobs allowed much longer plug life than stock, and I carried over that idea to the crusaders. HEI helps on the fringes: lean, hi-compr., oil fouled, carbon fouled, hi-rpm, low voltage, etc.
With HEI, carb, and intake manifold changes, I got 20-25% better mileage. I suspect that the carb did 90% of that.
 
Condender, you have two similar threads going right now.
I think that there is some ignition timing information in your other thread, that you may want to blend in with some of the concerns in this thread.
The sum of all, is going to get you closer to where you want to be with this.
IMO that is!

I also think that you are very hopeful that some of these proposed fuel economy, horse power and torque increases, are realistic........ as though being a result of an ignition change alone.

Just try not to get too caught up in seeking "like" support for an idea that may be "hear-say" only..... and from a source who's agenda is to sell you something that may not be completely necessary.
I'm not discounting that they may work, and may work very well.
Just a suggestion! :D

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Sorry about the 2 thread but they are 2 different things - i will try and stay on topic in each.

What exactly did you do to lean out the carb?

Thanks
 
contender31 said:
  1. Sorry about the 2 thread but they are 2 different things - i will try and stay on topic in each.
  2. What exactly did you do to lean out the carb?
Thanks
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  1. NO...... no problem with the two threads. I was referring to information in one thread, that may be beneficial to you in the other thread. IOW, just be sure to bring ignition timing into the equation here as you make any other changes.
  2. This needs to be fully understood. DO NOT lean out any High Speed circuits without knowing exactly what you are doing. (these require an internal change anyway) If leaning out the Low Speed circuits (external adjustment), that's an entirely different thing, with entirely different results. Results that will aid in low speed operation ONLY, and without affecting high speed fuel metering.
 
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