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Tom Kristensen walks through a perfect lap of Le Mans in Forza 5

One of the best ways of learning a new track, aside from driving it, is to hear someone that's intimately familiar with it give you a good walkthrough. That's just what you'll get here, as the winningest driver in 24 Hours of Le Mans history, Tom Kristensen, walks you through the Circuit de la Sarthe's high-speed, 8.5-mile strip of pavement.
Kristensen is dubbed over scenes of drivers from a Forza Motorsport 5 contest lapping the track at the wheel of an Audi R18 E-Tron Quattro, adding a bit of visual sense to the Danish drivers description of the track.
With the 2014 24 Hours of Le Mans kicking off this weekend, this is just the sort of video you'll want to watch to get you in the mood. Take a look below, and then let us know what you think in Comments.

Audi unveils A3 Sportback G-Tron with bi-fuel power, 808-mile range

By this time next year, the Audi A3 Sportback will be offered with a variety fuel-efficient powertrains ranging from diesel to the all-electric E-Tron, but perhaps the most interesting is the all-new G-Tron model, which uses Audi's innovative carbon-natural compressed natural gas called e-gas. Previously called A3 TCNG, we first heard about this technology last year, but now Audi has confirmed that this low-emission, sustainable-fuel will debut by the end of this year on the A3 Sportback G-Tron.
To create this e-gas, a plant in Werlte, Germany uses electricity to split water into hydrogen and oxygen. As hydrogen fuel cell vehicles become more popular, Audi says that this process could also be used to produce hydrogen fuel, but to create CNG, it mixes the hydrogen with carbon dioxide to create "synthetic methane." Since it is identical to the CNG available today, Audi's e-gas can be shipped and stored using the existing CNG infrastructure. Making the whole process even greener, Audi obtains the CO2 for this process from a nearby biogas plant, which would otherwise be released into the atmosphere.
Differentiated from the regular versions of the A3, the G-Tron features a pair of tanks under the rear cargo floor holding 15.43 pounds of CNG, which can power the car for almost 250 miles. What's more, the A3's conventional gasoline tank is still in place, giving the car an addition 560 miles of range. In total, that means the A3 G-Tron has a driving range of more than 800 miles. To run on both CNG and gas, Audi made changes to the car's 1.4-liter four-cylinder engine (including the turbo, cylinder head and fuel injection system) and catalytic converter.

Audi TT Ultra Quattro Concept throws lightness at the problem

Audi is celebrating the 2013 Wörthersee Tour with a special concept version of the company's TT. The Audi TT Ultra Quattro concept tips the scales at just 2,449 pounds thanks to some extensive engineering work. The company pulled nearly 95 lbs from the car's body structure and used carbon-fiber reinforced plastics for many of its detachable body components. As a result, the concept weighs in at a full 220 pounds lighter than its production counterpart. Throw in a wicked turbocharged 2.0-liter four-cylinder engine with 310 horsepower and 295 pound-feet of torque, and you get a machine with the power to weight ratio in the supercar realm. 0-60 comes up in 4.2 seconds and top speed is listed at 173 mph.
Inside, the TT Ultra Quattro features plenty of carbon fiber trim, and designers also fitted the seats from the R8 GT to save a little weight. The buckets use CFRP for the seat frames, saving nearly 50 pounds in the process. In a world where automakers seem blind to the negative effect of throwing more heft at a vehicle, we're in love with the Ultra Quattro concept. Check out the full press release below for more information.