I wait until the oil level shows two bars above minimum before adding one full quart. For city driving this equals 1000-1200 miles, and for highway driving it's about 1400-1500 miles.

Hey Split!
I’m on Aspen Drive, between you and Zip.
Ran into a Turbo S owner at dealer who also lives in Westbrook and just chipped and HRE’d his drive.
Also checked out a non-6speeder only 2 mile south with a 700GT.
Sort of a small pocket of forced induction, Eh?

Enjoy before it snows soon.

Riverbend Zippy. Not too far from you. Send me a PM and we'll get the cars out together before the white stuff falls.

Pedal to the metal doesn't help. I've seen you cruise. Mine is chipped up now, so lets race

Let's get a concensus on exactly how much oil 1 bar represents. I remember that the local dealer's SM told me once, but I can't remember. 8 oz/bar?

My manual says 1 bar = 1/4 L.

Well, then. 1L = 33.8 Oz. Then 1 bar = 8.5 Oz approx.

I have 5k miles on my 996tt, and lose a quart about every 800-900 miles. Will this get better, worse, or no change with more miles on my car?

dunno...but CONSTANTLY high(ish) consumption upon spirited driving seems pretty normal for these cars...

Turbos typically burn more oil than N/A engines. You're burning a lot of oil, but w/ in the range of what can be expected. I would make meticulous records of oil consumption and would be alarmed if you start burning MORE oil.
Also, I would not recommend trying keep the oil level to the top bar on the bar-gauge readout. For some reason these engines like a level somewhere between the half-way mark and low-end range.

My level is one bar below mid-way and will stay that way for a 1000 miles, but if I fill to the top bar it will burn down to mid-level in 500 miles.

Maybe someone can explain.