When I was at the Woodburn dragstrip a while back with my dad, we noticed that one of the dragsters sounded very different from the others. It buzzed instead of roared, and when you looked at it, the engine was very small and didn't have any sort of visible cylinders. We assumed it was probably a Wankel Rotary laying it down. Then when we went into the pits and happened upon the car, we discovered that it was a 3-cylinder, 800cc (or so) two-stroke snowmobile motor. It had three expansion chambers that we hadn't been able to see from the stands, and total weight of the car without the driver, was about 60% of total weight with the driver. This guy was duking it out against Chevy big-blocks, but had the same displacement as ONE of the cylinders found in the V8s. It was really something to behold.
