how much oil loss are we talking about? i had the good old tensioner failure which bent all 16 valves into an 'S' shape, i redid the head new valves and stem seals, pistons were ok etc, rebuilt her and runs lovely all except it was using half a gallon a week on 350 miles. something definitely wrong, took the head off again and it turned out to be the valve guides, oil was just pouring into the bores, so a local engine specialist did the head for me now valves all 16 skimmed new hydraulic lifters and valve guides and stem seals £165 bargain but now the piston has gone through the side of the bore.. ha ha and bent another 2 valves. Its all good fun, so heads back off and i need a bottom end