its a good thing i found this post. i just recently went to cobb stg 2 with a catless downpipe with my 2013 wrx. Same thing occurred like it did in the video. on cold engine start up, a large amount of white smoke appeared. And also, this was right after I did my first oil change at the dealer. when i smelled the smoke, it didnt have that sweet smell like it does with coolant, but more of a burning smell. like burnt oil or fuel. i checked the dipstick and the oil level was well above the recommended dots. so does that mean the excess oil is being burned off? i didnt do the oil change. the dealer did. other than that, the car runs fine. ive done a bunch of wot pulls with no knock or boost creep etc. car runs like a champ. im just a bit worried about that initial cold engine startup. could it be on what you guys concluded it to? blow by is it? is it fine to just run it as it?