I think an accurate measure of the prechamber volume vs. the combustion chamber volume at tdc is in order. This will give you an idea how much of the air is actually going in and out of the prechamber. I am inclined to believe that the combustion chamber volume is rather small compared to the prechamber. This would support the need to open up the prechamber for better flow. Cold start and noise are probably the two biggest negative outcomes. Who knows maybe power will also be negatively affected?? We won't know until someone tries. I would do it if I had a spare engine lying around.

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