i got a saph and just fitted some 8x18inch Mos tyre size 225/35 R 18 ofset being et 35

i had my archers rolled a bit but every time i go over a bump they hit the top of the arch and sometimes rub on the suspension, cornering is so much easier and safer but watch out for bumps

any ideas how i can make the arch higher so there is no rubbing when going over bumps??