oil consumption
P.S. I thought I'd remove the little inspection cover in my A4's bell housing to see if my rear main might be the culprit. Nope, drier than an 84 year old nun's *****.
LS1's have a shitty PCV system, you said you have NO PCV? They take the crank pressure out of the valve covers and blow it into the intake manifold, but it takes alot of oil with it. 3 or 4 qts low? woah... so you were running with 1.5-2 qts... no good. Check out your intake manifold and see how much oil you have in it, might invest in a catch can (homemade for what...30$?) or Thunder Racing sells them. There is also the LS6 PCV swap but it is certainly more work, however it should actually stop the oil consumption instead of just stopping the oil from getting to your intake manifold.
Either way, adding some oil at 2,000-2,500 to an oil change is normal, you could also try the GERMAN CASTROL solution which is said to help with the oil consumption, basically just using the special "European" castrol syntec oil instead of Mobil 1 or whatever. I don't like Mobil 1, its like water.

Read up my friend.
http://www.pistonslap.com/
Oddly enough my car doesnt have any piston slap, then again maybe the dynomax bullets drown it out


