Its been done, fairly recently in fact, involved a certain Chertsey based tuning company, an RS2 extra & some C&B cams. 201bhp at SRR iirc. Was running the map for the normal RS2, so would possibly have done more with a few mapping tweaks.
Not all the development work was put on the forumz yo
I believe this was James, he was telling me about this, holds some sort of record on a track iirc from what he was telling me