The challenge from Ford Motor Co.'s top brass was daunting: Take an old car and a bland one and make them better. Do not change their basic frames and footprints, but make them look and feel new. And by the way, the future of the company is at stake, because if they do not sell, the automaker could run out of money.

That's what Ford (F) designers and engineers faced when they set out to update the aging Focus small car and the slow-selling Five Hundred full-sized sedan.

The company will unveil new versions of both models this week at the North American International Auto Show in Detroit. A lot is riding on them when they hit the showrooms later this year as 2008 models, especially if consumers continue to shift from trucks and sport utility vehicles to cars.

Photo Essay: North American International Auto Show.

"Certainly there's pressure," Lon Zaback, chief designer of the Focus, said recently as he walked around the car explaining its new features. "I don't feel any anxiety about it at all because I think we've done a terrific job."

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Ford has mortgaged its assets to borrow up to $23.4 billion to fund a massive restructuring plan and cover billions in losses expected until 2009. The company, which lost $7 billion in the first nine months of last year, expects to burn up $17 billion in cash during the next two years.

Analysts say the company desperately needs sales to raise cash if it hopes to survive.

The compact Focus, first introduced in 1999, now looks old and clunky. The Five Hundred generally is perceived as good but underpowered and pedestrian.

First the company did market research to figure out what needed to change.

With the Focus, Zaback and the redesign team knew they would be limited by the car's current architecture in their efforts to modernize the company's entry in the small car market.

They raised the sheet metal on the sides, shrinking the window size to give it a sloping, sportier look, with horizontal creases in the sheet metal. There is more chrome on the grille, mimicking Ford's successful Fusion mid-sized car, and the hood became more rounded.

"The car appears to be a little bit shorter and have shorter overhangs. It has a much more sporty appearance because of some of the proportional things we did with it," Zaback said.

The interior is simple but modern with nicer seats, lighted cupholders and more expensive materials including a brushed aluminum look for the dashboard and blue instrument lighting.

The new Focus also is among the models to get the optional Ford-Microsoft "Sync" system that integrates cell phones and personal music players into the car's electronics, something Ford hopes will appeal to younger buyers.

"There's a night-and-day difference between today's Focus and the new one. We really improved it," said Greg Burgess, the vehicle development manager.

While the designers were at work, engineers were busy going over all the existing car's parts, refining the two-liter four-cylinder engine, steering and suspension. Although horsepower figures were not released, Ford said they made the car more powerful while reducing its weight by about 100 pounds. It will be at least as fuel efficient as the current model, which gets 37 miles per gallon on the highway, said Marcio Alfonso, the chief engineer.

The Five Hundred got a less-radical redesign with changes in the front grille and rear lights and fenders to make it look more sporty and more like the Fusion.

The body did not change much, but the car gets a modernized interior and a new 3.5-liter V6 engine with 60 more horsepower and a six-speed automatic transmission. It should be as fuel efficient and much quieter than the old one even though its zero-to-60 acceleration time is 1.5 seconds faster, Ford said. Market research showed that buyers thought the old versions were underpowered, Ford said.

It also will get optional electronic stability control, something that should get it back on the Insurance Institute for Highway Safety's list of safest cars, said Killol Bhuta, the car's marketing manager.

"It was always good. We just made it better," Bhuta said.

The Five Hundred, built on Volvo architecture, sold moderately well in 2005, its first full year on the market, but sales nose-dived last year from almost 108,000 to about 84,000, something Ford hopes the redesign will reverse. Focus also saw its sales drop last year to just over 177,000, down more than 100,000 from a peak of around 286,000 in 2000.

Ford said it has not set prices on either the Five Hundred, which hits showrooms in the summer, or the Focus, which comes in the fall.

Several analysts who have seen the new Fords say the changes are good steps but may not be enough to fend off sharper, newer designs from the competition.

Erich Merkle, director of forecasting for the auto consulting company IRN Inc. in Grand Rapids, Michigan, said the new Focus, for instance, still does not look as modern as Honda's Civic, which he considers to be the gold standard for small cars.

"It's a step forward, but it's not a dramatic leap," he said. "Unfortunately the competition is really moving forward in that segment."

He and Rebecca Lindland, an auto analyst at Global Insight, an economic research and consulting company, said Ford may not have had the cash to redo the Focus completely, a charge that Ford denies.

Merkle said Ford could have brought the superior European Focus to America instead of remaking the U.S. version.

"Ford does a lot of things that sometimes I just scratch my head over," he said.

Lindland likes the new Focus but said the Five Hundred still is too conservative to set it apart from competitors.

"In order to attract people into a showroom, you need to have something that's going to turn people's heads," she said. "It's not cutting edge at all."

The people working on the new cars, though, think otherwise.

"Our mind-set hasn't changed regardless of what our financial position is," said Beth Donovan, Ford's small car marketing manager. "We want to win."

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