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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.

2020 Nissan Maxima and Pathfinder Rock Creek | Autoblog Podcast #602

In this week's Autoblog Podcast, Editor-in-Chief Greg Migliore is joined by Consumer Editor Jeremy Korzeniewski and Assistant Editor Zac Palmer. This week, they've been driving the Nissan Maxima, Mercedes-Benz Metris Cargo Van, Mazda3 sedan and Nissan Pathfinder Rock Creek, and they talk about their experiences with those vehicles. Then, in the Spend My Money segment, they help a viewer from Autoblog's Twitch stream pick a used pickup. Autoblog Podcast #602 Get The Podcast iTunes – Subscribe to the Autoblog Podcast in iTunes RSS – Add the Autoblog Podcast feed to your RSS aggregator MP3 – Download the MP3 directly Rundown 2020 Nissan Maxima 2019 Mercedes-Benz Metris Cargo Van 2019 Mazda3 sedan 2020 Nissan Pathfinder Rock Creek Edition Spend My Money Feedback Email – Podcast@Autoblog.com Review the show on iTunes Related Video: This content is hosted by a third party. To view it, please update your privacy preferences. Manage Settings.

IIHS Top Safety Pick and Top Safety Pick+ awards get tougher: Here are the latest winners

Automakers love to trumpet the accolades from the Insurance Institute for Highway Safety, but the agency keeps making its best grades harder to achieve. For 2020, it is raising the bar again, requiring a better score in the passenger-side small-overlap crash test, wider availability of top-performing headlights, and automatic emergency braking systems that effectively avoid collisions with pedestrians, in addition to its previous benchmarks. Why the 2020 criteria is harder: To be named either a Top Safety Pick or Top Safety Pick+, the required performance in the passenger-side small-overlap crash test has been raised from Acceptable to Good, meaning that the model must achieve Good ratings in all crash tests. The Nissan Rogue, for example, scored an Acceptable in the passenger-side small overlap crash, and so it loses its Top Safety Pick rating for 2020. To achieve either of the top ratings, a vehicle's automatic emergency braking system must effectively avoid hitting pedestrians as well as other vehicles. (The automatic emergency braking system can be optional, but then the award applies to the model only when so equipped.) Any vehicle whose automatic emergency braking system does not include pedestrian detection would lose its TSP or TSP+ rating for 2020, the Ram 1500 being one example. To be named a Top Safety Pick+, the model can have no variant with headlights that achieve less than an Acceptable rating (most new cars have different headlights — often LEDs — that are exclusive to upper trim levels).