Over the last 10,000 miles I have been slowly but steadily increasing oil consumption.

At 272,000 miles I replaced my timing chain, it had ~13 degrees of stretch. I screwed up a bit and the chain was one tooth off.

At 276,000 I corrected the chain, and had the injection pump retimed.

Here is where I noticed the oil consumption. Until this point I used ZERO oil in 4,000 miles, I do mean zero. It started at adding a 1/2 qt in 3,000 miles now most recently the oil light is coming on as soon as 1000-1500 miles after an oil change, which is atleast 1qt. I am very concerned.

I have no more than usual visible smoke (very little). 99% of my driving is highway at 80 to 90mph - I have noticed it is using more oil the faster I drive.

Maybe it's my turbo? I really have no issues with the engine, it starts on a 1/2 crank and it's been 35F here one night. Still has good power, sounds great, I don't get it. There is no more oil on the street than usual, so I don't think I'm leaking it.

Help!