Hi guys, as above really. Had an immature moment with a BMW driver yesterday. He pushed me for 4 miles so in the end I gave in and showed him how we roll throughout this scenario I was very impressed with how the car performed, constant boost, no flat spots, very responsive and just overall on point in every way. Nice dense air yesterday so we were all go!! BMW driver was in the correct position for this scenario which was behind hearing a nice 7000 rpm exhaust note, unfortunately when we got next to each other he said "that goes well and sounds awesome (nice bloke) but, it's black smoking at top end". Now obviously I was gunning it, so smoke is going to be the case, especially with a decat pipe. Oil usage is normal, and it doesn't smoke on tick over but when I got the wife to boot it with me stood behind it, ther was a touch of black smoke near top end. is this something to worrie about?? Or am I looking too far into this?? After being a previous Subaru owner and changing engines more times than I change my underpants, I tend not to put anything to chance. Any help would be great.