While in Halfrauds the other day I had a look at the spark plug chart.
It lists the BKR6EK for 1.8 and the BKR5EK for the Turbo.
Had a look on sparkplugs.co.uk, and it confirms that the BKR5EK is the std plug for the Turbo and the BKR5EIX the Iridium one.
As I currently have the BKR6EIX in at the moment I may put these in the wifes car and get the correct ones for mine.
I always though the higher the number the colder the plug ....?