Chaparral is the only racing team that has the distinction of making it on this list of banned race cars twice. Way to go, guys.
The Chaparral 2J is one of the strangest race cars ever built, and it showcases the kind of imagination racing teams have when doing what it takes to win. The Chaparral 2J had two engines: a pretty unexceptional large Chevy V-8 that powered the car and an unexpected smaller engine. Why? The smaller engine drove two fans that pulled air out from beneath the car. That sounds utterly ridiculous until you realize that sucking the air out from under a car increases downforce and allows a car to corner better.
In effect, the Chaparral 2J had a tiny engine acting as an extra spoiler. Despite the car's many mechanical problems, competitors claimed the 2J's fans were illegal movable aerodynamic devices to thwart its impending success. The Chaparral 2J raced in the 1970 season of the Can-Am series, picked up a lot of wins and was quickly put out to pasture.