DETROIT – Paralleling General Motors Corp.’s quest for the “complete electrification of the automobile” will be the increased performance of its enthusiast-based models.

“We have tons (of technologies) on the shelf,” GM Powertrain Group Vice President Tom Stephens tells Ward’s on the sidelines of the North American International Auto Show here.

“We can deliver whatever (level of performance) is needed.”

Advanced electric-based vehicles and concepts such as the Chevrolet Volt plug-in concept, dominated NAIAS this year and foretell GM’s future product direction. But Stephens describes a diametric structure for future vehicles, where the auto maker’s mainstream models are flanked by niches of advanced, environmentally friendly vehicles and performance-oriented sports cars and sedans.

“Performance is alive and well (at GM),” he says.

The dichotomy is part of GM’s core plan for powertrain diversity, Stephens says, noting the auto maker will continue to develop conventional, alternative-fuel and electric-based engines and drivetrains.

Symbolizing this structure is GM’s commitment to performance brands within its mainstream vehicle lineups, such as the Chevrolet SS; Pontiac GXP; Saturn Red Line and Cadillac V-Series; all of which will grow stronger in the future, Stephens says.

Also of note is the next-generation rear-wheel-drive architecture being developed by GM Holden Ltd. in Australia. The platform will underpin several fun-to-drive models, Stephen says, including the new Chevrolet Camaro and Impala, both of which will hit the U.S. market later in the decade.

In addition, Bob Lutz, vice chairman-global product development, confirms at NAIAS Australian media reports that GM will export RWD, V-8-powered Holden Commodore SS models to the U.S. to be rebadged as Pontiac G8 sedans.

The Commodore has a long performance legacy Down Under and, in G8 guise, is expected to revive Pontiac’s ailing reputation for performance and excitement.

Media reports also indicate GM will unveil a more powerful version of the Corvette ZO6 within a year to better compete against the new 600-hp ’08 Dodge Viper, a possibility Stephens does not dismiss.

When prodded on the future of the small-block V-8 in GM’s lineup, he says fuel economy and refinement will continue to improve, as will performance.

“Supercharging is not a problem,” Stephens says of the ZO6’s 500-hp LS7 V-8, adding direct gasoline injection is a challenge for the small-block, but development work already has been built into its architecture.

As for the horsepower limits of GM’s mainstream, high-end vehicles, such as a “super” ZO6, Stephens says: “Integration is key. There are few limits if the balance is there with the chassis and the electronic stability controls.”

Stephens also promises the aging Northstar DOHC V-8, which has powered various Cadillac vehicles for more than a decade, will not go away.

“We plan to be more than competitive (with the Northstar) in horsepower, torque, fuel economy and emissions,” he says, declining to tip his hand on the specific future of the engine’s development.

msutton@wardsauto.com