on 2040-cars

Auto blog

Basic Continuously Variable Transmission explained with Legos

In recent years, the search for better fuel efficiency and smoother shifting has produced automatic transmissions with double-digit gears. Alternatively, the same quest has boosted the popularity and usage of a different type of automatic transmission without any fixed gears, the continuously variable transmission, or CVT. YouTuber Sariel's Lego Workshop recently took the time to build a CVT demonstration model out of Legos to help explain how they work. Sariel begins by showing the model's input and output shafts that are parallel to each other. Each shaft has a cone attached to it, and they are inversely placed so that the large part of one cone is next to the small part of the other cone. The two cones are connected using a rounded rubber band.  By shifting the rubber band up and down the cones, the machine changes the effective ratio between the cones. So, a 1:4 ratio can be smoothly transitioned to 4:1. No clutch is required to operate the mechanism, and it eliminates hitches or pauses between gear changes. CVTs are also advantageous over 9- or 10-speed automatics in that they are far less complex and weigh less.  To demonstrate how the CVT operates in a vehicle, Sariel used a joke about Top Gear. The original Top Gear is represented by a faster-moving car that has the rubber band around the large part of the cone on the input shaft. Top Gear without former hosts Richard Hammond, Jeremy Clarkson, and James May is represented by a slow-moving car with the rubber band around the large part of the cone on the output shaft.  For an even more detailed explanation of how CVTs work — albeit one that doesn't involve toys — you can click here. Technology Toys/Games Nissan Subaru

Xcar rates AWD vs. FWD vs. RWD

With snow and ice blanketing large swathes of the United States over the past few weeks, commuting hasn't been easy. Among some drivers, there's an ongoing debate about how much all-wheel drive really helps when it gets slippery and whether rear-drive is as bad in slick conditions as many people think. Xcar Films puts some of those beliefs to the test in its latest video by showing off three very different cars taking on a trio of low-grip challenges. Xcar's picks for the test include the fairly plebeian, all-wheel drive Subaru Impreza, the somewhat plush, rear-drive BMW 120d and the sporty, front-drive Renault Megane RS 275 Trophy. Things start out easy with a hydraulic plate forcing the back end out on a wet skid pad. From there, the tests get really interesting with a slalom on simulated ice, and the cars finish with a high-speed cornering challenge through a soaked turn. While an obvious winner emerges in the end, keep in mind this is hardly a scientific test of grip. For better accuracy, all three vehicles should be wearing identical tires, and the same driver should be behind the wheel of each one. Still, Xcar's examination is a fun chance to see how vehicles react when things get slick. News Source: Xcar Films via YouTube BMW Subaru Renault Driving Safety Videos xcar renault megane xcar films renault megane rs

Consumer Reports declares most and least loved cars [w/video]

Consumer Reports is crunching the numbers from its annual owner-satisfaction survey, and part of that process is finding out how attached drivers are to their cars. CR simply asks readers of models up to three years old if they would buy the same vehicle again in light of their entire ownership experience, and tallies the results. After looking at the responses for about 350,000 vehicles, it turns out that people really love a certain California-built, electrically powered luxury sedan. That's right, this year's the overall winner was the Tesla Model S with a whopping 98 percent of owners saying they would purchase another one (the Model S also won this award last year, with 99 percent satisfaction). The Chevrolet Corvette Stingray came in a close second with 95 percent of drivers hoping to park another one in their garage. A few models weren't quite so favored, though. The Nissan Versa Sedan was the least loved model among its owners; a mere 42 percent said that they would purchase another. The aging Jeep Compass didn't do much better, with just 43 percent of drivers willing to buy the softroader again. On average, about 70 percent of owners say they would buy their car again, and only four cars ranked below 50 percent in CR's findings. Check out the video above to see some of the winners and losers in a few of CR's categories. If you're a subscriber, you can check out the full list on its website. Related Gallery Consumer Reports Most Loved Cars 2014 Related Gallery Consumer Reports Least Loved Cars 2014 News Source: Consumer Reports - sub. req., Consumer Reports via YouTube Chevrolet Ford Mazda Mercedes-Benz Porsche Subaru Tesla Ownership Videos car ownership