Do factory equipped vehicles always have same size drums front/rear?

Too many forum members are eager to chime in to help despite their lack of knowledge on a subject. It is nice to want to help but passing out incorrect information helps no-one.
4 wheel drum systems have NO proportioning valve. They have a distribution block that only serves as a multi-port unit to distribute the fluid. The wheel cylinder sizes determined the proportioning.
I have never seen a staggered drum diameter front to rear but I have seen wider shoes used on the front.
R/T B bodies used 11" drums F/R as standard equipment. My '70 Charger had 4 wheel 10" drums. Of all the A body cars I have owned, I have never seen a 10" front, 9" rear drum arrangement.
If they ever were built that way, I have never seen it.