Ronald Reagan was president the last time Pontiac sold a rear-wheel-drive Grand Prix. The spiritual successor to General Motors’ performance sedan from the past arrives this week at the Chicago auto show, in the form of the 2008 Pontiac G8.

  Due in dealerships early next year, the all-new performance sedan shares underpinnings with the Holden Commodore from GM’s Australian subsidiary. Commodore went on sale in Australia in August 2006.

  Pontiac is now confirming what we reported a few weeks ago (“G8 Summit: Rear-drive Pontiac G8 replacement spied in Australia,” Jan. 22): Pontiac will sell two G8s, a base model powered by a 3.6-liter 261-hp, 250-lb-ft V6 with a five-speed automatic, and a GT running a 6.0-liter 362-hp, 391-lb-ft V8 mated to a six-speed automatic. Both trannies will feature manual shift mode; a six-speed stick (shown on the Chicago show car) will be available with the V8 sometime after launch. The V8 also will be equipped with Active Fuel Management, GM’s system that saves fuel by deactivating four cylinders during low-load driving. The GT also gets a standard