The drum that replaced the original [shocking i know but according to research i've had the original factory drums all these years] is more sleek or smaller in design? The self adjuster is dialed all the way back, meaning it's not expanded one bit. The brakes aren't tight when putting the drums on though, it seems to feel just right.
The shorter pad is where it should be so everything seems in check. I think it is a friction smell. It smells like smoking breaks but then has a somewhat sweet odor? if that helps out.