2000 Mazda Miata Base Convertible 2-door 1.8l 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.

Mazda Skyactiv-X Review | The revolution begins with a squeeze-bang

The matte black Skyactiv-X prototype looks like a rough Mazda3, perhaps reconstructed after a bad wreck by an over-enthusiastic owner of a spot welder and lots of gaffers' tape. Ribbed ducts poke out of the dash sending two breaths of conditioned air to no one in particular. Even its revolutionary engine, the thing we're here to experience, is entombed in a massive, nondescript cover to mask its unseemly noises. It's a wild, strange way to meet a very unconventional vehicle that promises diesel-like fuel economy, a wide torque band, and an exotic method for burning less gas than ever before. It takes a few hours for Mazda's engineers to explain the fundamental principles of operation. For more detail, read our Skyactiv-X Spark Controlled Compression Ignition explainer, but here's a very brief overview. Skyactiv-X marries some traditional gasoline engine characteristics with a novel form of compression ignition called SPCCI. The key for Skyactiv-X is to use very high compression in the cylinder and an extremely lean fuel-air mixture. Squeezed right to the cusp of getting hot enough to blow up all on its own (which is very hard to predict), a squirt of extra gas and a spark interject to cross that compression-ignition threshold in a controlled and predictable manner. See the animation below: That takes a few essential components to get just right. One is a massive amount of computer processing power and some pressure sensors in the individual cylinders, because the ambient conditions change how and when these things happen. Skyactiv-X uses a clutched supercharger to pump in additional air when needed to nail the mixture precisely, and high-pressure injectors to get the low ratios of fuel to disperse properly in the chamber. And since it operates like a conventional gasoline engine sometimes, it uses valve timing to lower the very high compression ratio so it doesn't reach combustion ignition in that mode. In practice, the Skyactiv-X runs in compression ignition mode most of the time. In practical terms, that means it drives like a torquey gasoline Skyactiv engine. The torque curve is broad and flat — diesel-like in that respect. That also means it can get away with using a six-speed transmission and a lower final drive for better response. There's enough grunt and economy together that Mazda can let the engine spin faster — at 60 mph, it's running at roughly 1,000 more RPM than a similar gas engine, with greater efficiency.

This is what a 1,200-hp twin-turbo 4-rotor looks like in a Miata

We've seen the diminutive Mazda MX-5 Miata swallow plenty of big engines, but New Zealand drifting ace "Mad Mike" Whiddett is roaring into where-no-man-has-gone-before territory. Wanting to replace his 515-horsepower "MADBUL" RX-7 and its twin-turbocharged, three-rotor 20B engine, his new ride is an NC-series Miata with four rotors and twin Garrett turbochargers courtesy of Pulse Performance Race Engineering. It is called "RADBUL," and expected power at standard boost is 1,200 hp, but the builders at Pulse Performance think it will get up to 1,500 hp at full boost. And yes, that exhaust exits through the hood. Four-rotor engines are actually popular - builds are detailed on forums like this one from 2007 and this one from 2008, this UK company or this Canadian company will sell you one complete - but they're usually being prepped for an RX-7. Mad Mike's choice of a Miata for this enterprise makes this about as extreme as you can get, short of throwing it into a Mazda R360. You can watch Mad Mike tell the story of the build in the video, and check out the first and second installments about the build on the Red Bull site.