I think this is just one of the mysteries of honda engines, i had a full rebuild on my B18C with 72k on it, i got new oil and compressions rings, valve seals, cam & plug seals, new head gasket, inlet/outlet manifold gaskets and basically every seal and O ring in the head replaced, i alsogot the valves re-ground, and a very mild p&p job on the head. I used mobil SuperS semi synth for the break in (approx1000 miles) and then changed the oil and filter again (still used mobil superS 10W 40) and burned very little for the next 800-1000 miles, then one morning i started the car up and heard a loud clicking noise like metal on metal, so popped the hood and checked the oil and it was reading on the lowest level, so it took a quart to fill it again, that was last week and i havent used the car much so its possibly still ok. But my point is, i have no leaks, and had all that work done, and the ******* thing is still using oil, i'm convinced its that **** mobil oil, and so thinking of switching back to regular castrol GTX this week, even though its only been about 1200 miles or less since my last oil change. I know the thing about not switching back to regular after using fully synth, but is it the same if your using semi synth oil. I realise this doesnt help the thread creator, but i just wanted to show that a rebuild wont necessarily cure the problem. BTW i had the work done by a shop that build honda rally cars and the mechanic that done all the work is especially respected in the rallying world over here. If it continues to burn oil after i switch back to regular then i'm getting rid of it, even though it would break my heart..BTW the cars a JDM integra SiVTEC (1994)