I have a 2011 Mini Cooper S N18. I'm thinking about adding an oil catch can. My question is do I need a filter (breather) on top or not?
Also, if this is a bad idea, or a complete waste of time, please let me know that as well.

 

No need for one on the N18 (at least that is what I have found on mine). Not gonna hurt if you want one but go with a closed, non-breather style if you do want to add one.

my $.02

 

I agree, no catch can required on a N18 . I used to check mine often and never had anything in it except condensation in the winter. In the summer it was always dry & empty.

 

I'm burning a quart of oil every 1000 miles!!!

That oil has to be going somewhere....?
I don't see it falling on the street. I don't see it burning out the back (grey, black, blue, etc.). So the only place I can think of it is coating my turbo and the intake manifold.

 

How many miles on your car ? I have 2 N18's both with about 60,000 miles on them. One does not use any oil between oil changes one uses about 1 pint. Oil changes on synthetic are done at 5,000 - 6,000 miles.

If it goes back into the turbo it's going to get burned anyway and send up some smoke on and off.

Do your plugs show evidence of oil burning ?

 

65K now
My plugs were dry and light brown. I kept a few of the better looking ones for emergencies and can toss a picture up if it helps. There weren't oil fouled or anything like that. Two of the four were in pretty good shape as a recall. Cylinder one was definitely done/finished though with parts of the electrode burnt off.

The oil comes off the pcv valve into the turbo and is then routed down to the inter cooler pressurized / to be cooled. I would think at that point, the oil will come out of the vapor state and be sitting at the bottom of the inter cooler as a liquid. That's just a guess. Anybody ever pulled off the charge line off the intercooler and see a "pool" of oil come out of the tube? I just bought this car two months ago. Looking at the design of the car...this is what I'm expecting.