The 3-2-1 method is actually 3 hours in smoke, 2 sprayed and wrapped in foil and back in the smoker, 1 still wrapped in foil and in a cooler.
I never do internal temps on ribs. I use the method that they are done when they pull back from the bone ~1/8 to 1/4 of an inch.
The 3-2-1 is good for good size racks of ribs, usually pork spare ribs. BB's usually only need about 4 hours depending on the size. Your small racks will not really work with the 3-2-1 method, becuase that is just too long.
Just play with the numbers. They are just a guide line. On small racks I usually do 2 hours in smoke and 1 sprayed then wrapped and back in the smoker. I have done alot of small racks because it seems like they are always a really good price.
In order of usage:
WSM - no mods.
NB Bandera - modded.
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