So after the last one met it’s fate fairly quickly due to a number of tuning problems I set about rebuilding the engine again, this is what happened:

Spent a good deal of my summer building the engine in my R53 Mini back up from scratch with the help from an American friend. Car now produces 293bhp and is good to rev up to 8.3-8.5K rpm, a full spec list can be found here. Nice little time-lapse of the build: