Corsa-B.uk - Vauxhall, Opel and Holden Corsa B Owners Club

hi there,
just bought a set of irmscher softstars in 6jx16 would i be right in thinking that the best tyre size is 195/45r16?
im going to be lowering it around 30-40mm at some pont and dont want any issues.
thanks

mines lowered 60mm on speedlines, dont have any issues unless i have more than one in the back