Chrysler develops case for a 300 convertible; engineering issues would create challenge MARY CONNELLY | Automotive News Posted Date: 4/11/05 The Chrysler group is developing a business case to determine whether it will build a Chrysler 300 convertible. Marketing and engineering groups are studying the Helios concept convertible created by ASC Inc. The Helios is based on a stock 300C sedan. "There is nothing in the segment," says George Murphy, Chrysler group senior vice president of global brand marketing. "It is an interesting opportunity." But Chrysler faces a daunting challenge in building a four-door convertible - a rarity because of the engineering difficulties involved. In November, Chrysler group design chief Trevor Creed said the company would not build a 300 convertible. Detroit unveiling Chrysler engineers were involved in the creation of the Helios, which was unveiled at the 2005 Detroit auto show. But Creed said structural-rigidity issues precluded a production version of the 300 convertible. The company has no deadline for making a decision, Murphy says. Chrysler has received "a lot of requests" for a 300 convertible, Murphy says."It is more a technical challenge than it is a marketing challenge," he says. But Chrysler will wait to deal with the engineering issues until a marketing study is complete, says Burke Brown, chief engineer for the rear-wheel-drive product team. "Right now, Brown says, "marketing is in the middle of their analysis asking, 'Is this really something the world wants and needs?' " Creating structural rigidity in a four-door convertible is a long-standing industry challenge. If Chrysler succeeds, the 300 convertible will be the first four-door convertible since the 1967 Lincoln Continental, according to ASC. Rigidity is an issue because removing the roof eliminates much of the structure that gives the vehicle body its stiffness. The longer distance between the front and rear wheels in a four-door vehicle makes it more likely the body will flex. Brown says the issue is: "How do you make a car with that long a wheelbase very stiff and not give up all the ride comfort and handling? "I don't think there is anything in it that is totally impossible. It is assessing what it will take." When it introduced the Helios, ASC said it had reinforced the car. Build decisions Additionally, Chrysler must decide how to build a convertible. "Do you take a whole car that is essentially a finished car and chop it up and throw away parts, or do you send out a partial vehicle?" Brown asks. ASC does not comment on programs with any customer, says Tim Yost, a spokesman for the Southgate, Mich., specialty design firm. ASC stands by claims it made in January regarding the structural rigidity of the Helios, Yost says. In January, the company cited patent-pending "body-engineering advances, including an innovative cross-car bulkhead, longitudinal tunnel and underbody reinforcements." ASC said the rigidity of the Helios would be better than existing production convertibles. ASC also said the Helios would meet federal side-impact crash standards.