Doug any tuning shop should have the tools to test the air / Fuel ratio. When I swapped my setup back to a carb setup, the shop had a pair of wands that were inserted into the tailpipes (sniffers) I think they were called. Sounds like a technical term to me. But it quickly showed the ratio.
In order to get the ratio correct in my car we swapped out the jets. My guess and it's just a guess is that the primary jets need to be larger????
I can recommend a shop but it's up here in nh. If you're interested I'll pass along the info
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