After some tyre advice to confirm my initial thoughts
My wifes Astra G currently has 225/35/18 fitted to a 8Jx18 40 offset wheels and we're currently getting a bit of arch rub at the rear.
My thoughts are that the tyres should be 215/35/18 is this correct and would a 215 tyre be ok on a 8J rim.
If I changed to the narrower tyre would this eleaviate the problem of the arch rubbing? Would this also help as I've got plans to drop the car by 30mm