Help me with uncountable
A have 3 loafs of bread, B has 1 loaf
Can I say
"B doesn't have as much bread as A "
or
" A has 3 times as much bread as B"

Question

Help me with uncountable
A have 3 loafs of bread, B has 1 loaf
Can I say 
"B doesn't have as much bread as A "
or
" A has 3 times as much bread as B"

Answer

yes, both are fine.

The plural of loaf is loaves.
1 wife 2 wives
1 life 2 lives
1 leaf 2 leaves

Answer

The plural of the collective noun, loaf is "loaves".  "Loafs" is a verb. It means to idle around.  "He loafs around too much".  
"Leaves" can be the plural of "leaf" or as verb to mean "go away", "depart".  He leaves her.

Since bread in not countable, you use "much".  So your sentences are correct.  However, "loaf" is countable.  So you must use "many".  B doesn't have as MANY loafs of bread as A