Eddy float question

So I have another post going about my total advance. I had a plate installed in my distributor that made my total timing when flooring it set to 32 with my initial at 16 and with high speed cruising around 48. Well I took that plate out which now makes my total when flooring it set at 42 and when high speed cruising with vacuum advance is now at 58!! That seems way to high but it makes it run much better! Now when I cruise at 3000 in 1st then floor it, she takes off great! However my buddy drove behind me and said he sees black smoke that was barely there before!?! (If i lean out the secondaries anymore it runs like crap). Why would more advance cause more smoke? And is that much advance doing any harm? Thanks for any help -kory