Motor Gadi

How the Tweel Airless Tire Works.....?

2011-09-05T09:42:00.000-07:00

Michelin first announced the Tweel in 2005. The name is a combination of the words tire and wheel because the Tweel doesn’t use a traditional wheel hub assembly. A solid inner hub mounts to the axle. That’s surrounded by polyurethane spokes arrayed in a pattern of wedges. A shear band is stretched across the spokes, forming the outer edge of the tire (the part that comes in contact with the road). The tension of the shear band on the spokes and the strength of the spokes themselves replace the air pressure of a traditional tire. The tread is then attached to the shear band. The Tweel looks sort of like a very large, futuristic bicycle wheel.

When the Tweel is put to the road, the spokes absorb road impacts the same way air pressure does in pneumatic tires. The tread and shear bands deform temporarily as the spokes bend, then quickly spring back into shape. Tweels can be made with different spoke tensions, allowing for different handling characteristics.
More pliant spokes result in a more comfortable ride with improved handling. The lateral stiffness of the Tweel is also adjustable. However, you can’t adjust a Tweel once it has been manufactured. You’ll have to select a different Tweel. For testing, Michelin equipped an Audi A4 with Tweels made with five times as much lateral stiffness as a pneumatic tire, resulting in “very responsive handling” [Source: Michelin].
Michelin reports that “the Tweel prototype… is within five percent of the rolling resistance and mass levels of current pneumatic tires. That translates to mean within one percent of the fuel economy” of the tires on your own car. Since the Tweel is very early in its development, Michelin could be expected to improve those numbers.

-Land Rover Beats BMW In SUV Segment--

2011-09-04T00:13:00.000-07:00

Land rover has beaten BMW in India in the SUV segment. Land Rover is priced very well in India from starting Rs 35 lakhs till Rs 1.11 crore while BMW SUV starting is from Rs 55 lakh.

Land Rover currently sells models including Freelander 2, Discovery 4 Sport Tourer, The Range Rover Sport and the Range Rover in India.

Land Rover has sold 35 units compared to 15 units by BMW in the month of January. Audi has sold 114 units while Mercedes sold 6 units.

“v r encouraged by the response 2 d Land Rover vehicles in India,” said Rohit Suri, head of premier car division at Tata Motors.

BMW is currently has plans to start assembling the X1 in India as a entry level SUV that will be priced competitively around Rs 26 lakhs.

Car sales in financial year 2010-2011

2011-09-04T00:06:00.000-07:00

Car Units sold Percentage Growth

Skoda Superb 4164 31.40%

BMW 5 Series 2901 99.90%

Mercedes C Class 2613 57.70%

Honda Accord 2446 -11.80%

Mercedes E Class 2437 69.60%

BMW 3 Series 2398 58.40%

Audi A4 1543 105.20%

Mercedes S Class 1131 119.20%

Audi A6 997 101.40%

Volkswagen Passat 660 28.20%

Toyota Camry 558 52.50%

BMW 7 Series 556 50.70%

Nissan Teana 230 31.40%

Audi A8 78 136.40%

Volvo S80 38 -51.30%

Volkswagen Phaeton 26 NA

Audi R8 23 155.60%

Volvo S60 23 NA

Porsche Panamera 22 175.00%

Porsche 911 13 NA

Porsche Cayman 10 42.90%

Audi TT 9 -25%

Porsche Boxter 8 166.70%

STORY OF A LEGEND CALLED "AC SHELBY GT"

2011-09-03T17:31:00.000-07:00

The formula for the success of the Cobra came through a man named Carroll Shelby adapting a powerful Ford engine into a nimble, British sports car.

A.C. Cars of Thames Ditton in Surrey, England had been producing the Ace since 1954. It was designed by John Tojeiro and featured an independent suspension by transverse leaf springs. The tubular frame body of the vehicle took its styling cues from Ferrari. The original engine used in the Ace was a 1991 cc, over-head-cam engine designed by John Weller, the founder of AC, in the 1920s. In 1956, an optional Bristol engine became available. This was a BMW derived, 1971 cc six-cylinder engine that was capable of producing 125 horsepower. With the Bristol engine, the Ace captured many victories on the race tracks around the world. It even won the SCCA Class E championship three years in a row.

In 1959, Bristol ceased its six-cylinder engine production. When Bristol stopped supplying A.C. with the engine, the production of the Ace ceased. Carroll Shelby quickly negotiated a deal where A.C. would supply him with the chassis. Now all Shelby needed was an appropriate engine. In 1961, Ford introduced the 221 cubic-inch small block engine. This was a new lightweight, thin wall-cast, V8 engine that produced 164 horsepower. Shelby approached Ford about the use of the engine for the 2-seat sports car. Ford agrees.

In February of 1962, a 260 HiPo engine and Borg-Warner four-speed manual gearbox was fitted into the aluminum-bodied Cobras. The AC Shelby Ford Cobra was complete.

In April of 1962, the first Cobra with chassis CSX 2000 was painted yellow and shipped to the New York Auto Show where it appeared on the Ford display. The vehicle was an instant success and attracted much attention. Orders came faster than Shelby could build. The prototype CSX 2000 was continuously being repainted for magazine reviews. The purpose was to create an illusion that more Cobras existed.

In 1963 the engine size increased to 289 cubic-inches. Rack-and-pinion steering was added to the vehicle.

Two Cobras were entered into the grueling 24-Hours of Le Mans endurance race. Carroll Shelby himself drove one of the vehicles. Ford had refused to provide an engine so Shelby, with the help of A.C. cars and Ed Hugus, prepare the cars. One of the Cobras managed to capture a seventh place finish, a major accomplishment.

Dan Gurney became the first American driver to win an FIA race in an American car when he won the Bridgehampton 500KM race in September of 1963 while driving a Cobra.

In 1964, the Cobra returned to LeMans where it finished fourth overall and first in the GT class.

Near the end of 1964, the Cobra 427 was unveiled to the press. If featured a new tubular, aluminum body, coil spring chassis, and a 427 cubic-inch, 425 horsepower engine. The car was able to go from zero to 100 mph and back to zero in less than 14 seconds.

In 1967, the last 427 Cobra was built and in 1968, the last 427 Cobra was sold by Carroll Shelby.

Ford had shifted their resources to the new GT40 and modified Mustang programs. In 1966, three GT-40 Mark II's crossed the finish line at Le Mans capturing first, second, and third.

ORIGIN OF TERM "HORSE POWER"

2011-09-03T17:20:00.000-07:00

The term horsepower was invented by the engineer James Watt. Watt lived from 1736 to 1819 and is most famous for his work on improving the performance of steam engines. We are also reminded of him every day when we talk about 60-watt light bulbs.

The story goes that Watt was working with ponies lifting coal at a coal mine, and he wanted a way to talk about the power available from one of these animals. He found that, on average, a mine pony could do 22,000 foot-pounds of work in a minute. He then increased that number by 50 percent and pegged the measurement of horsepower at 33,000 foot-pounds of work in one minute. It is that arbitrary unit of measure that has made its way down through the centuries and now appears on your car, your lawn mower, your chain saw and even in some cases your vacuum cleaner.

Q.What if I pumped pure oxygen into my car engine instead of using the air in the atmosphere?

2011-09-03T17:00:00.000-07:00

ANS.The air around us is about 21 percent oxygen. Almost all the rest is nitrogen, which is inert when it runs through the engine. The oxygen controls how much gasoline an engine can burn. The ratio of gas to oxygen is about 1:14 -- for each gram of gasoline that burns, the engine needs about 14 grams of oxygen. The engine can burn no more gas than the amount of oxygen allows. Any extra fuel would come out of the exhaust pipe unburned.
So if the car used pure oxygen, it would be inhaling 100 percent oxygen instead of 21 percent oxygen, or about five times more oxygen. This would mean that it could burn about five times more fuel. And that would mean about five times more horsepower. So a 100-horsepower engine would become a 500-horsepower engine!