I have the same problem with oil bleeding past turbo , especialy under boost , used a oil siphon unit to cure the smoking , works great , run 2 minutes on start and stop, looking for turbo pressure solution , used 8mm restrictor , rebuilt the garret turbo , where can I find those parts listed by r33 racer , like to get in the know as to how it came out on both , after Dyno did the fix hold? , what was the final fix? Duncan , did you get the oil solved on your sporty as well.