2007 Saab 9-3 ConvertibleClick to enlarge picture

The 2006 and 2007 Saab 9-3 Convertible with two doors and a cloth top earned the same "Top Safety Pick" label as its sedan counterpart with a fixed steel roof.

But it has happened to two Saab cars.

The 2006 and 2007 Saab 9-3 Convertible with two doors and a retractable fabric roof achieved the same "Top Safety Pick" label after frontal, side and rear crash tests as its Saab 9-3 sedan counterpart with permanent, steel roof.

The crash tests were the first ever on convertibles conducted by the Insurance Institute for Highway Safety , an insurance industry group based in Arlington, Va. Even the federal government's National Highway Traffic Safety Administration has yet to test any of the 10 midsize convertibles that the insurance institute tested. So the IIHS ratings are the first indications in the U.S. of the crashworthiness of these open-top cars.

The IIHS "wanted to … see if crashworthiness improvements in mainstream cars also are being built into convertibles," said Adrian Lund, IIHS president. "For the most part, we found that this is happening."

The 2007 Saab 9-3 sedan has a starting manufacturer's suggested retail price of $26,250, while the starting price for a 9-3 Convertible is $37,495. Saab, which is owned by U.S. automaker General Motors Corp., is based in Sweden and has had a reputation for safe vehicles going back decades.

Convertibles From Two Swedish Brands Are Leaders
The only other "Top Safety Pick" of the 10 convertibles crash tested were the 2006 and 2007 Volvo C70, developed by another Sweden-based automaker.

Like the Saab 9-3 Convertible, the Volvo C70 earned "good" ratings in the three IIHS crash tests. But it cannot be directly compared to a sedan version, because there is no C70 sedan.

All "Top Picks" had to have standard rollbars designed to preserve headroom if a car rolls over in a crash. They also had to come standard with electronic stability control that can intervene when it detects a car is about to skid.

As with the Saab 9-3 Convertible, Volvo's C70 is a low-volume seller that has not been crash-tested by the U.S. NHTSA.

Starting retail price for a 2007 C70 is $39,090.

Audi A4 Cabriolet Needs a Redesign
Just because a convertible comes from Europe, however, does not mean it does well in crash tests, IIHS officials learned.

IIHS said the 2007 Audi A4 Cabriolet, which starts at $39,100, was only marginal in side crash testing and thus wasn't a "Top Pick." However they expect the next-generation A4 Cabriolet to do better because it will get improved engineering with safety and structural updates.

How do they know? Audi is part of German carmaker Volkswagen AG, and the 2007 VW Eos convertible, introduced as a new model in calendar 2006, had better side crash test results in the IIHS evaluation. The Eos comes with a standard retractable hardtop and has a starting retail price of $28,110.

Can't Judge Safety Just by the Price
The price difference between the better performing but lower-priced Eos and the Audi A4 points out another finding from IIHS's testing: Price doesn't necessarily guarantee superior crashworthiness.

Indeed, one of America's lowest-priced convertibles—the 2007 Mitsubishi Eclipse Spyder with a fabric top has a starting retail price of some $25,000—tied VW's Eos in overall crash-test ratings and rated better than the Audi A4 and the 2007 BMW 3-Series Convertible.

Like the Eos, the Eclipse earned "good" ratings in frontal and side crash testing and "marginal" for rear crash protection.

Despite its starting price of more than $43,000, BMW's 2007 3-Series was "good" only in frontal crash tests. It was rated "marginal" in side crash testing and "poor" in rear crash protection, the IIHS said.

The 3-Series was the highest-priced convertible tested by the Insurance Institute.

Note that there are several higher-priced, luxury convertibles that were not among the 10 vehicles selected for this first convertible evaluation by the IIHS. These include the Bentley Continental GTC, Mercedes-Benz SL two-seater and the Cadillac XLR.

Top Sellers Rate About Midpack
But the insurance group made sure to test America's two top-selling convertibles—the Ford Mustang and the Chrysler Sebring.

With a starting retail price of $25,470, the Sebring was the only 2008 model tested because it debuted as an early 2008 model in spring 2007, just in time for the IIHS tests. It's also the only convertible in the U.S. that's offered with a choice of vinyl, cloth or retractable hardtop roofs. The IIHS test vehicle was a base Sebring with vinyl top, spokesman Russ Rader said.

But the Sebring Convertible earned "good" ratings in frontal and side crashes and only "poor" for rear crash protection.

This put it just above the 2004 to 2007 Toyota Camry Solara Convertible, which has a starting price of $27,190 for a 2007 model, and ahead of the 2007 Ford Mustang Convertible, which starts at $24,075.

Pontiac's G6 Convertible the Worst
The insurance industry put Pontiac's first convertible with retractable hardtop, the G6 Convertible, at the bottom of the list of 10 vehicles tested.

The 2007 G6 open-top model was "acceptable" in frontal crash testing but was the only one of the group to rate just "marginal" for both side and rear crash protection. And the test car included front seat-mounted side airbags.

But unlike side airbags in some of the other models, those in the G6 were designed to protect front passengers' chests and torsos, not heads. As a result, the crash dummy's head in the G6 hit the side windowsill with a severity that could lead to a serious skull fracture and brain injuries, the IIHS said.

And the G6 Convertible's driver seat came loose from one its floor tracks during the frontal crash, according to the IIHS.

Watch Out for Rear-End Crashes in Convertibles
In all except for the Saab 9-3 Convertible and Volvo C70, the worst ratings for each convertible were in rear crashes. The IIHS pointed to poor seat design and the need for quality head restraints in open-top cars.

"It isn't hard or expensive to design a seat to prevent neck injury in a rear-end crash," Lund said. "Some of these manufacturers … already have seat designs elsewhere in their lines of vehicles that are rated good for whiplash prevention, but these automakers haven't put the good seat/head restraints in their convertibles."

For detailed information on how the testing was conducted, visit www.iihs.org.

Safest Convertibles (among 10 midsize models tested)

1. 2006 - 2007 Saab 9-3 Convertible
2006 - 2007 Volvo C70 (tie)

3. 2007 Mitsubishi Eclipse Spyder
2007 Volkswagen Eos (tie)

5. 2008 Chrysler Sebring Convertible

6. 2004 - 2007 Toyota Camry Solara Convertible

7. 2007 Ford Mustang Convertible

8. 2007 BMW 3-Series Convertible
2007 Audi A4 Cabriolet (tie)

10. 2007 Pontiac G6 Convertible

Source: Insurance Institute for Highway Safety.

Ann Job is a freelance automotive writer.

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