DETROIT – After languishing at the bottom rung of product development during the 1980s, vehicle design, both exterior and interior, is returning to prominence at General Motors Corp., Vice Chairman Bob Lutz says in a keynote speech at the Ward’s Auto Interiors Show here.

Lutz, who heads global product development for the auto maker, says for decades GM had missed the point of both elegant and functional design when it came to vehicle cabins.

Some executives considered a vehicle’s interior as the prime place to save money, he says.

“The last happy hunting ground where a vehicle line executive could claw back the cost is the interior,” Lutz says.

Interior design was such an afterthought in GM culture, he says, that it took a while to convince a company executive he was being promoted, not demoted, when he was moved to the interior design leadership slot.

But GM’s design chief says interiors now are one of the few remaining areas where auto makers can differentiate their vehicles.

“It’s the last place in the world where you want to advertise the cheapness of your product,” he says. “It’s no longer permissible or possible to strip the interior.”

Lutz makes it clear GM won’t accept anything less than top quality from its interior suppliers. He cites an example of interior moldings, which a few months after production can begin to give off a sheen similar to that of “bacon grease” and cheapen the vehicle’s interior.

That’s evidence of suppliers overusing mold release agents to speed up production, he says.

“You can’t quote (for business) on that basis anymore, because we’re going to catch you,” he warns suppliers in attendance.

That’s because the interior can literally make or break the sale, he says. “You have to know very intimately what the customer wants. Give customers what they want and they’ll eat it up.”

GM wasn’t always so bad at design, he says, noting the opulent looks of the ’53 Chevrolet Corvette.

Today, he says, GM is trying to create “harmony” between the interior and the exterior.

The Hummer H2, Lutz says, is designed to have a functional interior that complements the vehicle’s purpose, while the forthcoming Buick Enclave cross/utility vehicle’s interior is designed with luxury and a sense of nostalgia and warmth in mind.

The new Chevrolet Tahoe also has rebuffed less expensive plastic and gray tones and features a more flowing center console, he adds.

“If you’re doing a $20,000 car, I believe you have to design for a $30,000 (vehicle),” he says.

That includes some design slight of hand, such as using metal foil to conceal plastic outlined gauges and cup holders or employing thinner seats to increase cabin room, he says.

Lutz quickly flashes a slide of the new Cadillac CTS interior, which includes thinner front seats.

At the same time, more and more consumer electronics, from iPod jacks to power outlets to run laptops or radar detectors, are working their way into vehicle interiors.

For his part, Lutz doesn’t like the idea of turning a car into a multimedia center, even though GM is offering more of those options on newer models. He cautions that too much technology can muddy up the vehicle-driver interface and backfire with customers.

“I believe a lot of these (interior technologies) are invented for one reason and one reason only: to drive people crazy,” he says. “It has to be about added value, not added headaches.”

scanderson@wardsauto.com