Infiniti understands the recipe for big luxury sedan success in the U.S. – rear-wheel drive and a V8 engine. True, there has to be plenty of luxury and technology heaped on top, and it’s gotta wear the right badge to satisfy the image-conscious, but under it all has got to be at least eight cylinders capable of spinning the rear tires.

In terms of luxury, the 2006 Infiniti Q45 Sport has the bases covered. Inside are seats covered in rich leather, a standard navigation system, a thumping Bose sound system, and lots of heated this and power that. Visual and engineering upgrades for ‘06 include 19-inch alloy wheels and rear active steering derived from the M35 Sport, a rev-matching automatic transmission (also first used in the M), and a sport-tuned suspension. Under the hood, however, is the same 340-horsepower V8 currently used in the Q45. And, because of that, the 2006 Q45 provides a feeling of underwhelming power, especially with that Sport moniker in mind.

During our brief test drive of the Q45 Sport, it was obvious that this large sedan could move out with authority, but at the same time, the 340-horse rating rang of optimism – maybe they’ve all been chewing on a little too much hay. However, looking past the engine character, drivers will surely notice the tighter handling and its ability to turn sharp highway on-ramps and twisty two-lanes into good fun.