Developing the 2016 Mazda CX-9

Mazda reckons that about 80 percent of its midsize three-row crossover will be sold in North America. So the development was executed in the U.S. by a group of people who are committed to real-world driving, not the stuff of window stickers and brochures.

According to Masashi Otsuka, vice president, Mazda North American Operations, R&D, the all-new, second-gen, 2016 CX-9 is a vehicle that is North American-centric. Although the vehicle is being built by Mazda in Hiroshima, approximately 80 percent of all of the seven-passenger, three-row crossovers will be shipped to North America. He says, “Normally at Mazda, most development work is done in Japan. But the planning, design and development was done in North America from the start. The development was led by the U.S. team.”

Another difference is that while Mazda has been rolling out a number of stylish cars and crossovers with the Kodo design language for the past several years, vehicles that have pretty much been centered on competing in the center of the market, the CX-9 is meant to be, according to Otsuka, the “flagship” for the brand, meaning that while there are the Touring and Grand Touring trims, they’ve gone even higher with the Signature trim. This is manifest in such things as the use, for the first time at Mazda, of Nappa leather on the interior. And Julien Montousse, director for Design at Mazda North American Operations, points to the use of real aluminum and actual wood from a tree, rosewood (sourced from Japanese guitar maker Fujigen), not from a vat of polymer.

The CX-9 is designed and engineered with a level of care that is truly outsized given the fact that Mazda is a company with a small percentage of the U.S. market, 1.8 percent in 2015, according to Autodata (motorintelligence.com).     

On the other hand, you get the sense from talking to people like Montousse, vehicle development engineer Dave Coleman, and Matt Valbuena, an HMI and Infotainment engineer, is that because Mazda is a small organization (comparatively speaking), there is a nimbleness and a bias for execution that is uncharacteristic of many companies (inside auto or out), and extraordinary efforts to do things that ideally exceed what the bigger companies are doing with but a fraction of the physical resources. But they have creativity, imagination, capability and common sense in spades.

Consider, for example, the development of the Skyactiv-G 2.5T engine, which was specifically designed for the CX-9. Listen to Coleman: “We decided to focus on the real world use of the car and how it is actually driven. What is typically advertised in catalogs, the 0 to 60 time and peak horsepower, is often at odds with what you want to do to make a car drive well in the real world.

“So we decided to ignore competitive specs and go for what the car is going to do in the real world. Real world fuel economy rather than EPA label. We decided to focus on the directness of the throttle response and controllability of the engine rather than peak horsepower.”

Consider the risk. Some customers look at the window sticker to see what the fuel economy numbers are. Some customers look at the ads in Car and Driver to see what the horsepower ratings are for the vehicle and its competitive set.

Yet this development team decided that the CX-9 is going to be driven by real people in the real world, not by denizens of Flatland.

The previous generation CX-9 is powered by a 3.7-liter V6 that produces 273 hp. The new CX-9 is powered by a 2.5-liter, turbocharged I4 that produces 227 hp. Which leads to a bit of a digression: Coleman points out that the new engine produces 250 hp when it is run on 93-octane—a.k.a., premium—fuel. It produces 227 hp when it is run with 87 octane. Regular. Coleman maintains that real people are likely to try 93 for a tank or two, then 87. And they’ll discover that in terms of their actual daily driving, there isn’t a whole lot of difference so they’ll probably opt for using regular gas. (And save about $0.50 per gallon in the process.)

The reason why people will discover that there isn’t a whole lot of difference is because of what they decided to focus on (in addition to improved fuel economy, and yes, according to the EPA sticker, they have achieved a best-in-class 22 mpg city/28 mpg highway/25 mpg combined for a front-drive version): torque.

“We decided to back off on horsepower to get more torque,” Coleman says. Whereas the 3.7-liter V6 delivers 270 lb-ft of torque at 4,250 rpm, the 2.5-liter I4 delivers 310 lb-ft at just 2,000 rpm. Coleman suggests that most people—unless they’re driving an RX-8 or something—stay below 4,000 rpm.

One of the things they did during the development of the engine was to take a European-spec CX-5 diesel, then re-tune the engine to get the sort of torque curve they wanted for the CX-9. Then they added mass of the vehicle so that it would be approximately that of the 2016 CX-9. (And here it might be appropriate to note that the curb weight of the 2016 CX-9 is lighter than the 2015 model: for a FWD vehicle, the new is 4,054 pounds vs. 4,323 pounds for the old, or 269 pounds; for AWD, it is 4,301 pounds new, vs. 4,449 pounds old, or 258 pounds. The new engine contributes to much of that weight reduction, as it is 132 pounds lighter than the V6.)

Because they were developing a family vehicle, one of the places they took the modified CX-5 was to schools, where they followed moms and dads picking up their kids. Coleman remarks, “These people were in a hurry to get to soccer practice.” But they, too, were getting on the throttle looking for torque at low rpms.

So how did they get to the 310 lb-ft at 2,000 rpm?

Coleman says that the alternatives are an “enormous naturally aspirated engine” or a highly boosted smaller engine. Clearly the first alternative wasn’t in the plans. But he goes on to explain that they wanted the turbocharged engine to feel like a giant, naturally aspirated engine: they didn’t want turbo lag, which is the consequence of getting the cycle started of the engine throwing off the exhaust that’s used to spin the turbine to produce the air that’s forced into the combustion chamber. They essentially created exhaust flow plumbing that at low speeds ports the exhaust gas through a restricted opening that creates more pressure (Coleman likens this to using your thumb to restrict the water coming out of a garden hose). And they also created a 4-3-1 pulse converter manifold that draws the exhaust gas out in a manner that is analogous to the way paint is drawn up and into the airflow of an airbrush.

"One dirty secret of turbos,” Coleman reveals, “is that they typically don’t make the fuel economy numbers that they promise.”

He explains that the reason this tends to be the case is because under high loads there is a thermal management strategy often employed that is based on injecting additional fuel into the combustion chamber: “Paradoxically, more fuel makes the combustion cooler.” It also wastes fuel. However, given the nature of the EPA drive cycle, which is comparatively gentle, that fuel enrichment strategy doesn’t come into play, so the EPA numbers for turbocharged engines are good. But Mazda engineers were working for “real world” performance. So they are using a cooled EGR system to manage the temperature. “It’s a well-understood principle,” Coleman says. But if the goal is to get good window sticker numbers, then it is irrelevant. The EGR approach allows the use of a 10.5:1 compression ratio.

As previously mentioned, the three-row CX-9 is a “family” vehicle. But the Mazda developers discovered something interesting about what people who are looking at vehicles in this category are interested in. It once was that the scales were entirely weighted toward family interests for vehicles like the CX-9, with the individual driver having little consequence. But perhaps it is because of Mazda’s own focus on the importance of driving (it will probably be among the last companies to introduce an autonomous car when that time comes), but they determined that people are interested in more of a balance between the individual and the family, so when Julien Montousse set about to design both the interior and the exterior of the CX-9, they worked to address the functional needs of families (ease of access to the third row; the ability to have a child seat in place in the second row while providing access to the third), as well as a sense of performance and fashion: “Compared to the old CX-9,” he says, “which was maybe more submissive, this time we wanted it to represent Mazda in a very proud, very stylish manner.”

And all evidence points to the fact that they delivered.