Tunnel ram carb tuning

I can't say I really know enough about emulsion tuning but I would think the more and larger diameters would lean it up no? Like you said counter intuitive. More air same fuel means lean. I've seen quite a few posts that say 28 is a good starting point for emulsion jetting. I was surprised to see the 450s had 27s, but it is a small cfm carb. But whatever, the air fuel ratio at cruise is 15.5 to 1. Could be the air bleeds? The 600s were fixed. Not for long. I'll get them to work, but 900 cfm may be adequate for my street car. Already ripped up the shock crossmember again. Is this a common B body thing? I know ....wrong forum.