2005 Mazda Mx-5 Mazdaspeed Convertible. 1 Owner. Less Than 31,000 Miles!!!!! on 2040-cars

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Confirmed: Mazda Miata gets more power, higher redline, telescoping wheel

Our friend over at Road & Track, Bozi Tatarevic, has a keen nose for stuff just like today's Miata news, and he spotted an article by the Japanese car magazine Car Watch that details Mazda's upcoming updates. Car Watch actually got to drive the car, too. There's a lot to go through, but the highlight has to be confirmation of what we told you earlier this year about a significant power bump: The Miata will indeed get an increase of 26 horsepower, from 155 to 181. But the power's not the whole story. Mazda has increased the redline from 6,800 RPM to 7,500. It's not clear at this point where torque and power peaks are in the rev range, or how these changes affect low-speed drivability, but more revs are almost always a good thing and aren't likely to detract from the roadster's fundamental goodness. Car Watch reports that lighter pistons and connecting rods are fitted to help reduce rotational mass in the 2.0-liter inline-four. Some valvetrain changes were needed to support the higher redline, mainly stiffer valvesprings to prevent valve float. Mazda also changed the shape of the valves and optimized the intake ports to breathe better at higher RPM. The inner diameter of the exhaust ports were increased to flow better through a new muffler better tuned to the engine's new operating range. This confirms and gives a little more detail to what we reported earlier based on a leaked document from Mazda Canada. Car Watch also confirms that the revised Miata will get a low-inertia dual-mass flywheel, which should help absorb some vibration, noise and harshness from the higher-revving engine without losing too much of the directness that a single-mass flywheel provides. Mazda usually gets stuff like this right, so while we won't know until we get a chance to drive it whether the DMF feels "right," we're not too worried about it. There's also a telescopic steering wheel, a first in any Miata, which has a range of about 1.1 inches. That doesn't sound like much, but it should help folks with longer legs reach the wheel without having to crank the seat forward. Interestingly, Car Watch reports that the telescoping wheel was opposed by some in the company seeking to save every fraction of an ounce of weight, and to get it through, the company apparently had to change some of the material in the upper steering column from steel to aluminum to satisfy the weight-conscious. Little details like these are fantastic.

Honda may recall up to 1M vehicles for airbag issue, following Toyota's lead

It seems Toyota won't be the only one recalling the faulty Takata airbag inflators for long. Honda insiders in Japan claim that the company is getting close to announcing its own worldwide campaign that would begin before the end of June.
Unnamed sources close to Honda in Japan tell Automotive News that the company is pursuing an internal investigation into possibly affected models and is working with Takata to gather more information. They claim that it could involve even more than the 1.14 million cars worldwide that the automaker covered under the first recall for the problem in April 2013, including 561,000 vehicles in the US.
Toyota jumpstarted this process last week when it recalled over 2 million cars worldwide, including 844,277 in the US. Soon after, the National Highway Traffic Safety Administration began a preliminary evaluation into the issue following six reported incidents, and started assembling data about potentially affected models from Toyota, Honda, Mazda, Nissan, Chrysler. NHTSA also began investigating Takata itself.

Mazda files patents for a sequential twin-turbo setup

Mazda has a history of interesting engine technologies, from yesterday's rotary engine to tomorrow's compression ignition engine, and new patents show it still may have some internal combustion tricks up its sleeve. The one on display in these patents isn't especially new in concept, though. A sequential twin-turbocharger setup is something Mazda itself used on the third-generation RX-7. But it's something we haven't seen much of lately. It looks like it could have some possible advantages over older sequential systems, and it has some potential advantages for enthusiasts. First a quick and dirty primer for what makes a sequential twin-turbo system distinct from other twin-turbo systems. In many twin-turbo engines, there are simply two turbos that work together as one bigger turbo. They're the same size, and they spool up at the same time. With a sequential setup, at low rpm, a smaller turbocharger is spooled up first at low-rpm for quicker throttle response, and as the rpm and exhaust pressure increases, a valve opens up that allows a larger turbocharger to also spool up and provide high-rpm boost. That's basically how the Mazda design shown above functions. A big flap blocks off the larger turbocharger exhaust inlet, channeling all the exhaust to the smaller turbo. When more exhaust is available at high rpm, it looks like that flap opens up to spool up the big turbo, too. What's interesting here is that the way the turbochargers are packaged takes up less space than past systems. It looks like both turbos are contained in one unit that shares the same exhaust outlet, meaning the exhaust manifold could be kept simple and compact. In fact, the piping for compressed intake air could also be shared, reducing the amount of piping, which would further decrease the amount of materials and possible failure points. There are a number advantages of making this system smaller. The potential applications of the system are much greater, since it could fit in smaller cars with smaller engine bays. Making the system smaller also means that there won't be as much weight, which is important from both fuel economy and performance standpoints. Finally, the smaller setup likely uses fewer materials, which could make the system cheaper and thus easier to offer on a wider range of vehicles, or at least more profitable for Mazda.