I own a 98 SLK230 Kompressor. I recently purchased a vortex generator from Ebay. The idea is that if air spins through the intake, it reaches the engine with greater saturation of the intake tube and greater velocity. For ten bucks, I thought I'd give it a shot.

The results were surprising. Prior to installation, there has always been an irritating delay between when I mash the pedal and when the engine responds. The vortex generator seems to have reduced that delay. Also, the car has more power. I don't have stats, but I could feel the difference. It is also supposed to improve gas mileage, (which is why I bought it) and I don't know yet if it does, but its worth the ten dollars.