I've only done a systematic evaluation of fuel consumption on the trip from Norfolk to Grenada this Fall. I had the newly repitched fixed prop on the boat. In different sea conditions I noted 3.5-4.0 liter/hr consumption at 1600, 1800, and 2000 rpm, some of which was motoring and some motorsailing, some heading into the sea and some with light wind astern. At 2200 rpm the consumption jumped to 5.5-6.0 liters per hour. I haven't run it faster than that long enough to have a feel for consumption at higher rpm.
I do run the engine at maximum rpm (2850 with that prop and a clean hull) for about 15 min every 6 hours. After burning 3/4 tank of fuel on the way down there was some soot on the port topside aft of the exhaust, but nothing that wouldn't be expected according to a mechanic who was looking at my genset. When running hard there is no increase in smoke coming from the exhaust that I can see. Running the Volvo as described, there is virtually no oil consumption. I haven't had to add oil except when changing oil and filters since I've owned her.