Hi, my line coming in is ¾ pex (48 PSI + 9.6 GPM specs) going into pre-assembled 1 inch orbit valve manifolds (mod:91206) , should I proceed with ¾ in pipe leaving the manifolds to my 2x orbit Voyager II ¾ sprinkler heads or up it to 1 inch pipe. Will going bigger to 1 inch make a difference (reduce pressure loss, GPM,etc) even though the heads are ¾ or stick with ¾ pipe?

Thank you