GM Considers Four-Door Buick Avista Coupe

If Buick's glamorous Avista concept is approved for production, it will be as a four-door coupe. That's the hot tip from insiders who confirm a model of a four-door Avista exists inside GM's design studios in Warren, Mich.

After the Avista concept's reveal on the eve of the 2016 North American International Auto Show, GM execs were quick to point out any decision to put the car into production would depend on developing a viable business case. The Avista concept has a lot of enthusiastic supporters inside GM, including chairman and CEO Mary Barra, but many believe stretching the wheelbase and adding a couple of doors is key to getting the car approved for production.

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More practical than a regular coupe and less staid than a regular sedan, four-door coupes, pioneered in the modern era by the 2005 Mercedes-Benz CLS, have proven to be more than a short-lived fashion statement, having attracted a growing number of players since, from Porsche with the Panamera, to Volkswagen's CC, Audi's A7, and BMW's 6 Series Gran Coupe, which accounted for almost two-thirds of 6 Series sales in 2015. And more are coming: Jaguar is said to be working on a four-door coupe to replace the XK now that it has the F-Type to offer its sports car customers.

Compared with a conventional coupe, a four-door offers the prospect of relatively stable sales volumes over a longer time period, plus the opportunity to position Buick alongside premium brands in one of the few non-SUV vehicle segments that has shown growth over the past decade. An Avista four-door coupe is therefore seen by supporters inside GM as a safer bet than the two-door.

Making the Avista a four-door coupe would also give Buick a vehicle format that's unique in the GM product portfolio. "I think we've earned the right to have the halo car in the Buick range," says Duncan Aldred, vice president of Buick and GMC. Buick marketing manager Rob Peterson says, "A lot of smart people are looking at it."

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With sales of 1.25 million vehicles last year, Buick is now GM's second-best-selling brand worldwide after Chevrolet, and with the addition of the Envision SUV to the lineup, the Buick range is now composed of three sedans and three SUVs in the largest-volume segments in the industry. Significantly, Aldred makes it clear that when the Opel Insignia-based Cascada convertible, Buick's current halo car, reaches the end of its lifecycle -- probably three years from now -- it will be replaced with a new car.

Although the two-door Avista show car is built on a mashup of GM Alpha and Omega parts, a production version would likely use the Alpha architecture that underpins Cadillac's ATS and CTS and the new Chevy Camaro. Alpha gives GM a lot of flexibility in terms of powertrains and vehicle dimensions.

Exterior designer Chip Thole says the Avista bubbled out of the studio to explore Buick's bandwidth after the Avenir sedan went after the elegant end of the spectrum. Thole says the Avista concept was created to be a lightning rod for the brand and stretch the sporty side of Buick "for here and abroad." Although its 110-inch wheelbase makes it smaller than the full-size Avenir, Thole insists it would still be possible to add two more doors. He wanted the purity of a two-door coupe for the concept and says it was designed that way from the outset.

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China, which accounts for about 80 percent of total Buick sales, is a critical factor in any decision to build the Avista, be it a two- or four-door. But GM does not have to rely solely on demand from China and North America, the only two markets in which Buick is sold, to make a production car viable. The Alpha architecture and Avista's design language, including the reimagined Buick grille, mean it could easily be marketed in Europe as an Opel and right-hand-drive versions sold in Britain and Australia as Vauxhalls and Holdens.

The Avista concept featured GM's new 400-hp, twin-turbo, 3.0-liter V-6 under the hood mated to an eight-speed automatic transmission. This would likely be the default powertrain choice for the U.S. market and for premium versions of the car elsewhere, with all-wheel drive available as an option. GM's 275-hp, 2.0-liter turbo-four could be the base engine for all markets outside the U.S., and performance versions could use a variant of the 464-hp, 3.6-liter V-6 from Cadillac's ATS-V. Alpha also means a six-speed manual could be made available.

There'll be no V-8 Avista, though. GM sources say the Avista engine bay has not been protected for the 6.2-liter small-block even though it's used in the Alpha-based Camaro.