Eleven of the 13 cars tested got a "poor," the lowest of four ratings, according to the Insurance Institute for Highway Safety.
The Chevrolet Cobalt and the Toyota Corolla earned the second-highest rating of "acceptable," but only when they were tested with their optional side air bags. They earned "poor" ratings without the air bags.
Other vehicles that earned a "poor" rating were the Hyundai Elantra, Kia Spectra, Mazda 3, Mitsubishi Lancer, Nissan Sentra, Saturn Ion, Suzuki Forenza and Suzuki Aerio.
The institute's test simulates a severe crash. A barrier designed to resemble the front of a pickup or sport utility vehicle hits the side of the vehicle at 31 mph. A "poor" rating means a high chance of serious injury in a similar crash.
On The Early Show Monday, the vice president of the institute's vehicle research center, David Zuby, told co-anchor Julie Chen about three of the test scenarios, from the testing site in Ruckersville, Va.
The three cars were chosen by the institute to illustrate that cars must have a combination of a strong structure and side air bags to provide crash protection. The three are the Chevrolet Cobalt, Mitsubishi Lancer and Volkswagen New Beetle.
The Cobalt got an acceptable rating. The lesson is that a strong structure and side air bag helped.
The Lancer got a poor rating. It had no air bags and a weak structure; the side pillar was split.
The VW Beetle got a poor rating. It had good airbags, but a weak structure (the test dummy's head was okay, but not the torso and pelvis).
The institute isn't the only organization that does crash tests. The federal government does, too, and often there are big differences between the federal test results and the institute's. In some cases, cars listed as "poor" by the institute fare much better in the federal crash tests. But that's because federal testers use a simulator that is lower, more like a car. The institute uses one that mimics an SUV.
Four of the vehicles in the latest institute testing (the Elantra, New Beetle, Forenza and Spectra) have standard, head-protecting side air bags. But the institute's chief operating officer, Adrian Lund, said the cars had poor structure that failed to prevent injuries to the torso and pelvis.
Several of the vehicles offer optional side air bags, but the institute will only test those vehicles without side air bags unless the manufacturer provides a second vehicle with the option installed.
Toyota Motor Co. provided the Corolla with side air bags and General Motors Corp. provided the Cobalt and Saturn Ion. But even when it was tested with its optional side air bags, the Ion got a "poor" rating because the institute said it didn't adequately protect the driver's lower body.
GM said in a statement that the Cobalt and Ion meet or exceed all federal vehicle safety standards and got higher ratings in the institute's frontal crash tests.
The institute was most critical of the Neon, saying the car performed so poorly that the driver likely wouldn't have survived the crash. DaimlerChrysler AG defended the Neon, saying it meets federal safety standards and its performance is similar to other small cars.
"No single test can determine a vehicle's overall safety performance or how the vehicle will perform in a specific crash," DaimlerChrysler said in a statement.
Lund said the ratings were similar to frontal crash test ratings for small cars in 1997. Since then, manufacturers have redesigned those cars and now most get the highest safety rating in frontal crash tests.
"As manufacturers redesign their vehicles, we expect that small cars will get better in the side-impact test too," Lund said.