1.5 rear 1.5 centre and 1.9 front as per standard, the thing has done a bundle of racing, but with an n1 pump. i pulled the engine today, and fitted a -12 rear drain but not sure how far to cut back the top end feed, the vtc is still used and the power delivery is 11 hundred revs earlier with it, so i dont want to disconnect it, even with the 6 speed it hopeless at the track with out it. How far can you cut back the oil flow. im only running 70 psi hot.