The 603 was fitted with a 205VR15 radial tyre, and the Britannia and Brigand with a 225/70VR15.
The big coupe sibling to the 412 convertible, the 603 brought a fastback saloon style, with more internal room, and a more modern feel to the 412's underpinnings and mechanicals. A subtle and exclusive means of transport for the well-heeled. The Britannia update rapidly morphed into the Brigand, which had turbocharging and a cleaner style for the 80s.