Torch set-up question

hello all, i have a new torch set-up: uniweld, it was for acetylene
& oxygen but i converted it to propane & oxygen. i have the model 71
handle, model 17 #2 tip. My question is what is the psi range for the
propane and oxygen from regulator to tip? currently, i have it set
to 7 psi propane, 20 psi oxygen - but i feel the flame is too big.
is it that the psi is too high or i need a smaller than #2 tip? i am
working with sterling and fine silver currently, 18 - 20 gage. thanks
for any info.

gloria