Our spies have captured a thinly disguised Lexus LF-A prototype as it was heading to the Nurburgring race circuit for further testing about a month before the Japanese automaker officially unveils the V10-powered supercar at the 2009 Tokyo Motor Show, which runs from October 23 to November 8. The LF-A has been making the auto show rounds since 2005 when the coupe version was first revealed at the Detroit Show and was followed later on by a roadster concept.

These latest photos reveal that the design of the production model remains remarkably faithful to the concept with only minor modifications such as the less prominent side scoops and front fenders, and the replacement of the front-column-mounted rearview cameras with conventional mirrors.

The front end of the LF-A has also received a subtly makeover but it is most likely that many of these changes were made to improve the vehicle’s aerodynamics.

Power is said to come from a high-revving 5.0-liter V10 producing over 500-horsepower which should allow the first Lexus-badged supercar to hit the 100km/h (62mph) mark in under 4,0 seconds and top out at around 200mph or 320km/h.

Just like Mercedes-Benz recently revealed SLS AMG Gullwing, the LF-A features a front-mid engine, rear-wheel drive layout. The V10 engine is paired to an automated manual gearbox with paddle shifters.

Rumors from Japan suggest production will be strictly limited to 500 units, 120 of which are destined for Japan at an estimated price of around 30 million Yen a piece ($328,000 US – €222,000 at the current exchange rates) or about twice as much as a JDM Nissan GT-R V-Spec.

There was also a report from Japan’s Best Car early this year claiming that Lexus is also planning to develop an even more pricier and exclusive version of the LF-A that will be motivated by a 5.5-liter V10 delivering well over 500 horsepower.