Grind Size and Water Temperature for Natural Beans for 500ml brewing at V60

Is it true should I grind my Natural Beans medium coarse(Chemex Size) instead of medium fine and use 90-93C water instead of 95-97C for brewing 500 ml(2 cups) v60 brewing? I tried James Hoffmann V60 recipe with my Sumatra Mandheling beans(washed, we hulled) It finished 3:30 as James said but I tried it with my Brezillian Natural beans(Cocapil cooperative's Sabia and Arara beans) It finishead nearly 5 minutes even on my second try I could not make last pour(200 ml) fit into dripper.