You know you are basically comparing a '67 Graduate with 4 wheel drum brakes and no power to 2013 Camero with 4 wheel disc power disc.
Single pivot brakes worked great for 50+ years.
You did just use Kool Stop Campi style brake blocks right? you didn't put completely new holders (aka some new fangled low profile) stuff right?
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk