On Saturday I took my car for a drive north a few miles, mostly on 45MPH arterials with fairly light traffic. As I got on the freeway for the return trip, I was behind a late-model Camaro whose driver put the pedal to the metal, so I did likewise, getting up to 90 (indicated) and staying there. I stayed at 90 for about 4 miles before hitting heavier traffic, and cruised the rest of the way home. I'm certain I never abused the clutch or got near the rev limit (even though my tach reads way low). And I've driven the car harder than that. When I backed into my garage I noticed a strange and strong odor coming from the back of the car. I opened the engine cover (as I usually do, to let everything cool off) and the odor was more intense. It was an odor I had never encountered before, and I have no idea what it was. I checked to see any leaks but couldn't see any, and the garage floor stayed as dry as always. I took the car on several fairly short trips on Sunday, taking it easy and watching the gauges. The car felt and sounded just fine and the gauges all read normally. The smell has subsided but not gone away completely. If I had to describe the odor, the closest I could come to is: burnt oil? But the oil level in the engine reads fine, the oil pressure and temperature were normal on my Sunday drives, and the dipstick smells normal as well. Any guesses?