The Ford Duratec GDI engine is built to Euro 6 emissions standards, and changing anything might have consequences , since this is an incredibly set of rules to comply with.
As I understand it , the cat being as close as possible to the exhaust ports is to ensure maximum temperatures to burn off the volatile emissions very quickly.
The Librands kit moves the car outside the engine bay (good for keeping the car cooler, and for looks) but it does mean the cat is functioning at a lower temperature, which may not be beneficial. I don't know of any actual emissions data from either of the 2 suppliers of this type of system for the +4 GDI , so maybe the temperature difference is insignificant in the greater scheme of things , but I would be wary of such modifications.
If my memory serves me correctly I believe we have a member here who fitted a system to his car , but when it came to the MoT he reverted back to standard in order to ensure a pass.
