Infiniti is the luxury division of Nissan and the Infiniti FX50 is the V8 version of their midsize vehicle. Nissan, itself, started out as DAT motors in 1914, soon became Datsun and, in time, Nissan.

Infiniti started in 1989 with the first FX models replacing the QX4 in the 2003 model year. From the start the FX was larger than most midsize cars, as Infiniti sought to incorporate some aspects of the SUV, as well as some aspects of high performance vehicles, into it.

The numbers in the FX models refer to the engine size. It has always come in both six-cylinder and eight-cylinder models. Initially it was the 35 and the 45, which designated the 3.5 liter V6 and the 4.5 liter V8. The V8 was 320 horsepower and both engines were coupled with a five-speed automatic transmission with a "manual mode."

Not much changed from the initial offering through 2008. There was a minor refresh in 2006 and, of course, updating the standard and optional features was ongoing. But the engines remained the same. In fact, mileage dropped from 15 miles per gallon in the city and 19 on the highway to 13 in the city and 17 on the highway during the first generation of the FX V8.

The FX35 still carries the same size engine, though improved, but the large FX was given a new engine and a new name beginning in 2009. From that time, it became the Infiniti FX50 and sported a 5.0 liter 390 horsepower engine. The transmission on both models is now a seven-speed automatic with overdrive. Mileage has actually improved with the horsepower and the FX50 gets 14 miles per gallon in city driving and 20 miles per gallon on the highway.

The exterior of the FX was also substantially upgraded for the 2009 model year, though it retains the catlike look from previous models, described by the company as looking like a "bionic cheetah." From the start the V8 FXs have been all-wheel drive, while the V6 has offered the choice of all-wheel or rear wheel.

The next step for the Infiniti FX50 is the FX50 Sport, due out sometime in the 2010 model year. It will keep the 5.0 liter engine, but supercharge it to 490 horsepower.

NHTSA safety ratings are not available for the FX50. IIHS ratings are G straight across the board, which is the best rating they offer.

As noted, the Infiniti FX50 is a luxury vehicle, and it has a luxury price, starting at $58,400. That's well above the price for most midsize cars, of course, but not so much for luxury cars.