Are 4/4 wires different to the wires on my 2012 Plus 4
The difference is in rim widths. Standard 4/4 wires are 5" rims and originally came with 165 section tyres but you can go up to 185.
+4's AIUI usually have 5.5" rims with 185 section tyres on, but you can go up to 195.
I have seen +4s with 6" rims (max tyre 205) but I can't imagine they'd be very pleasant to drive.
The important limiting factor is tyre clearance against the main spring.
