Your .067 nitrous jetting setup should have a .034-035 fuel pill. Do you know the orifice size your solenoids? Your -4 line should be go to up to around a 200 shot. But a 200 would do better with a -6 line.
Are you running the same plugs for the different pill shots?
What plugs and gap are you at?
I would assume you have some timing pulled of course.
But you could be blowing through the converter. That is a strong possibility
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