Sorry for the grave digging, but this is closest relevant thread that I could fine.
I picked up a set of BKR7E plugs, I was surprised to find out that these are for the I5 AAN motor. When I got home I measured them with the a stock that came in my new from VW motor. It is alot shorter, unfortunately I have to use plugs with a removable top due using AEM/CBR coils with a twin fire ignition. The Bosch side fires are an AAN plug that has a removable top. I will probably use those, they worked great with my B5 S4.
I have done some searching to no avail. Has any used these? They are same car as the BKR7E, they have an excellent track record in the S4 community, unfortunately they are about $8 - $14 dollars more depending on where you get them.
Stock on from new motor on top, BKR7E and Side Fire on the bottom.
BKR7E and Stock fitment on old junkyard head. The stockers protrude a lot further in the bowl, the NGK (and the Side Fires would) sit flush with the bowl and plug body.