I was at the Blackhawk museum in my area on Saturday for a lecture from an owner of a 1922 Rolls Royce Silver Ghost that was in last years Great American Race. The owner says it uses a quart of oil every 150 miles. Talk about oil consumption!
I would say that sounds just about like our 1998 Chevy K2500 pickup. A quart a week is about right for our truck. We have no clue where it goes but it goes. Truck does not smoke, does not leak, runs great and the plugs look normal and not like an oil burner would. It now has 150K on the clock and we got the truck with 40K on it and its used oil heavily ever since we got it.