I have a turbcharged Lexus IS300, and just went to the track this weekend. I ran my car hard, but did not push it to the limit. I can go 17 psi max, but only ran it at 12.5 psi. Well, I checked my oil level today and noticed it was a bit lower than normal, but nothing major. I refilled it, drove to get some dinner and checked it again then I noticed it had some bubbles on the dipstick. I thought I overfilled filled it, but I only added about 1/4 of a quart. hmmm...then I cleaned the oily dipstick with my two fingers, rubbed my fingers together then noticed the oil felt different...maybe less viscous?. Upon further examination I found shiny tiny metal particles in the oil from the dipstick! I have come to a conclusion that I probably blew my headgasket because I was low on oil and the bubbles are from the water/antifreeze in the oil and the metal particles are probably from my bearings or so. ...very sad Could there be any other explanation? Could it just be fuel contamination? I have been tuning my car and it has been idling excessively. Car is running strong and normal, no blowby and the exhaust smoke looks normal. btw this is Redline 10w30 and was the first time my engine saw Redline Oil!!! I had switched from Mobil 1 TDT 5w40.