For decades, Porsche (PSHG_P) has had two things to thank for its strength: a narrow focus on performance sports cars and an independent ownership. It didn't spread itself thin trying to be all things to all people, and unlike Mercedes (DAI), BMW (BMWG), Jaguar, and other iconic car companies it neither acquired other brands nor allowed itself to be acquired.

But now things are changing on both fronts, and the question is whether Porsche can still be Porsche.

Porsche riled many fans six years ago when it launched the Cayenne SUV. Now the company is getting ready to launch later this year a four-door sedan. This comes at the same time Porsche is being swallowed by Volkswagen (VOWG), joining the VW stable of brands that includes Audi, Bentley, and Lamborghini.

"I don't like the changes because I'm a Porsche purist," says Pat Fallon, chairman of Fallon Worldwide in Minneapolis, whose ad agency handled Porsche's U.S. advertising in the 1980s and early '90s, and BMW's ads after that. "I have no doubt that the car is amazing, because that's what the culture at Porsche demands. But from the standpoint of brand focus, Apple would not be introducing a new dictaphone even if it's loaded with the newest technology."

Tradition of Independence Wendelin Wiedeking, CEO for 16 years at Porsche until he agreed to retire last month, long promoted Porsche's independence as critical to the company's success and Porsche's image. And by independence, Wiedeking did not just mean staving off a merger. He was also famous for rejecting state subsidies to build Porsches or their engines in Germany. "Why should we take money for doing what we were going to do anyway?" he said when he turned down government incentives a decade ago.

When asked at the 2002 Paris Auto Show if the automaker might be better off financially to be acquired by a larger automaker, Wiedeking said: "And just who has that worked out for so far? I can't think of a single one of these deals that I would have done, whether you are talking about BMW acquiring Rover, Mercedes buying Chrysler, or Ford (F) buying Volvo."

Yet oddly enough, Wiedeking is the author of both moves that now challenge Porsche's long-standing image. The company was forced into the Volkswagen deal because Wiedeking's scheme to buy Volkswagen backfired, leaving Porsche with more than $14 billion in debt it could not handle. Wiedeking's subsequent departure was a foregone conclusion. And Wiedeking was the driving force behind the development of the Panamera sedan, which will hit showrooms starting in October.

Perhaps not surprising, given the reception the Cayenne received back in 2003, the Panamera—which will top $100,000 for many buyers when they add various features—is being greeted with horror by many analysts, writers, and auto buffs.

The main criticism of the Panamera is its rear design. The roof line is somewhat bulbous, done so as to seat two adults comfortably in the back along with luggage in the trunk. Porsche executives believed it was crucial to make the car comfortable and practical, as well as fast and nimble.

Corporate VW Under the Skin But Peter Delorenzo, editor of the AutoExtremist blog, has compared the car to the AMC Pacer hatchback of the 1970s. And Delorenzo is skeptical that Volkswagen will be a good caretaker of the brand, despite the fact the companies have long worked together on vehicles. "After Porsche is absorbed into VW, watch for an entry-level Porsche in the $35,000 range, and then watch for creeping commonality as Porsches become more corporate VW under the skin," wrote the critic recently.

Porsche needs the car to win over buyers, if not critics. Porsche's sales were down 50% in July from a year ago, as the recession keeps many buyers on the sidelines. At the Concours d'Elégance at Pebble Beach, Calif., this month, Porsche had a helicopter on hand to zoom potential buyers from the links at the famed golf club to another luxury-laden golf club nearby, or to the Laguna Seca race track to drive the car.

Porsches are not known for their fuel economy, but Porsche installed a stop-start system that shuts down the Panamera's engine at stoplights and then kicks on again when the driver touches the gas pedal. It is a fuel saving of only a few miles per gallon (government fuel-economy ratings for the Panamera aren't out yet). Porsche has also said it is developing a Toyota (TM) Prius-like hybrid system for a later date, though a hybrid Panamera won't get nearly the Prius' fuel economy.

It is doubtful that Volkswagen would have approved the Panamera had it owned Porsche four or five years ago. It already markets cars through Bentley and Audi that will compete against the Panamera. But VW is fully vested in the car and will supply its body shell, while Porsche handles the engine and assembly at the same factory that builds the Cayenne. Porsche plans to build about 20,000 Panameras a year to sell worldwide.

Massive Horsepower Whatever people may think of its looks, the Panamera does have Porsche power. There's a 32-valve, DOHC 4,806cc V8 engine under the hood. It's rated at 393 horsepower at 6,500 rpm and makes 369 pound-feet of torque from 3,500 rpm to 5,000 rpm. Twin turbochargers pump the output of the Turbo model's V8 to 493 hp. That comes with a seven-speed, dual-clutch PDK automated manual transmission. Porsche says the Panamera S should get to 60 mph from a standstill in a bit less than 4.0 seconds. Unfortunately, in a very un-Porsche-like move, no manual transmission will be available.

Pricing starts at $89,800 for the S model, rising to $93,800 for the 4S and $132,600 for the Turbo. Prices of the various options will be set sometime before the car's official introduction on Oct. 17. But the 2009 Cayenne Turbo lists carbon-ceramic brakes at $8,840 and PDCC active stabilizer bars at $3,510.

That's a stiff price to pay for any sedan. Porsche—and now VW—have to hope there are enough well-heeled buyers out there with another spot to fill in their garage, next to the sports car and SUV.

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