Thanks Chris
Get on a tyre size calc site. Stick in the OEM tyre size and then the new tyre size and compare. You want to aim as much for as little difference as possible.
http://www.etyres.co.uk/tyre-size-calculator.htm
Front:
660mm - 225/45/18 (OEM)
654mm - 245/35/19 (New wheel)
6mm difference or 0.91%
Front:
678mm - 245/45/18 (OEM)
675mm - 275/35/19 (New wheel - stretched a bit?)
682mm - 285/35/19 (New wheel - not stretched?)
3mm difference or 0.44% OR 4mm or 0.59% respectively for 275 and 285
Sorry I was refering to the "most members" bit. Agreed that your tyre sizes are fine, thats what I said in my first reply, that you dont have a problem as your tyres sizes are fine. The point I was making was to the OP and that you cant blindly put 40 profiles on, you need to understand the relationship first, which no one has explained. People usually come unstuck by not understanding this and just swapping tyres willy nilly