SKYACTIV—Pushing boundaries and proving results

MANILA, Philippines - As Mazda continues to expand its SKYACTIV range in the Philippine market, it also puts these groundbreaking technologies to the test via the Mazda SKYACTIV Experiment.

What was once a blueprint for Mazda’s future direction now takes center stage at Mazda showrooms around the world. SKYACTIV has made a successful transition from philosophy to cutting-edge technology, and its key benefits of improved fuel efficiency and unfaltering performance continue to redefine not just Mazda’s growing range of SKYACTIV-equipped models, but also the way the world gets around on four wheels.

“Downsizing and a more eco-conscious approach to motoring make up the prevailing trend in the automotive industry the past decade,” says Steven Tan, president of the country’s official Mazda distributor, Berjaya Auto Philippines, Inc. “SKYACTIV is the route that Mazda has taken toward that end. It is divergent to the approach of most other manufacturers, but from the outset, the results have been very positive.”

The SKYACTIV Approach: An overview

The SKYACTIV technology is not confined to a single aspect of the car, but instead encompasses all the design and engineering principles, processes and techniques that go into vehicle production. This comprehensive strategy ensures that the integral components complement each others’ functions to maximize the technology’s gains.

By itself, the SKYACTIV-G gasoline engine’s headline improvements over Mazda’s conventional motors are as follows: 10% less weight, 30% less internal friction, 15% lower fuel consumption and CO2 emissions, and 15% more torque at low and midrange revs. It achieves these gains via a radical rethink of the internal-combustion engine, with the revised design including a high 13:1 compression ratio, a 4-2-1 exhaust layout, gasoline direct-injection (GDI), and continuously variable sequential valve timing (dual S-VT) on the intake and exhaust. The effectiveness of the design is such that the engine does not suffer from knocking issues that usually come with a high compression ratio. Moreover, it can run on regular 91-octane unleaded fuel without any performance trade-offs.

The i-STOP start/stop idling feature and the SKYACTIV-Drive automatic transmission then build upon these engine improvements. Both systems have been designed to operate in a seamless manner for quick response times and less energy usage. For instance, i-STOP operates not via the starter motor but through the “combustion start method,” which halts the pistons at the optimum position when it cuts off the engine, then injects fuel directly into a cylinder to force a piston down and restart the engine in just 0.35 seconds.

SKYACTIV-Drive, meanwhile, has a torque converter with a Full Range Direct Drive clutch mechanism that enables an early lock-up between the engine and the transmission. The result is a quick-reacting automatic gearbox that provides smooth and steady acceleration, but can also downshift with very minimal lag for quick bursts of speed.

Finally, the SKYACTIV-Body and the SKYACTIV-Chassis supply a light yet rigid platform that makes best use of the powertrain’s efficiency and potential. High-tensile steel comprises a large part of the body and the underpinnings. A new framework design and the latest construction methods strengthen the structure and bring down its weight even more, improving vehicle safety, fuel economy, and driving dynamics.

Tailored technologies: Regenerative braking and precise All-Wheel Drive

Apart from incorporating SKYACTIV, each Mazda vehicle also boasts specific features that make it even better equipped for its intended purpose and environment.

The Mazda6 midsize sedan’s main territory is the city and its stop-and-go traffic, so the i-ELOOP brake-energy regeneration system has been put in place to extend the engine-shutdown time under i-STOP and boost fuel economy by roughly 10%. It is composed of three parts specially designed for this application: a variable voltage alternator, an electric double-layer capacitor, and a DC/DC converter.

When the driver lifts off the accelerator pedal and applies the brakes, the alternator generates electricity at up to 25V to fully charge the capacitor in a matter of seconds. The system turns off the alternator when the car begins moving again, and the DC/DC converter adjusts the voltage of the electricity stored in the capacitor from 25V to 12V. It then uses this to power the vehicle’s electricals, thereby reducing the engine’s load and recycling the energy that would have otherwise been lost under braking.

In the case of the Mazda CX-5 AWD Sport, the emphasis is on surefooted handling in mild off-road conditions. Its all-wheel drivetrain with a precise slip detection system takes care of this requirement thanks to a front-biased setup that instantaneously shifts to all-wheel-drive mode when it detects slippage on the front wheels. Because the maximum front/rear torque split of 50/50 is activated only as needed, the CX-5 AWD Sport is still capable of matching the fuel-consumption figures of front-wheel-drive SUVs.

Expanding the range: The Mazda CX-5 Pro

In line with its worldwide thrust of completing an all-SKYACTIV vehicle lineup, Mazda makes another addition to its local SKYACTIV offerings with the CX-5 FWD Pro. Serving as the new entry-level variant of the CX-5, it is geared for the urban lifestyle.

“While the CX-5 FWD Pro has the same 2.0-liter engine (155ps at 6,000rpm, 200Nm at 4,000rpm) as the initially launched entry-level variants and is also driven by the front wheels, it adds the i-STOP system to its list of features,” Tan explains. “We have noted that in the Philippines, many SUVs are predominantly city mainstays, and that means they spend a lot of time sitting in gridlock. The addition of i-STOP will thus further add to the former entry-level variant’s already impressive range.”

Also standard in the CX-5 FWD Pro are the SKYACTIV-Drive 6-speed automatic transmission; 17”alloy wheels with 225/65 tires; power-folding side mirrors with body-color covers and integrated turn indicators; leather seats; a 6-speaker multimedia setup with Bluetooth voice control function; and a rear-view camera. Safety equipment includes ABS with electronic brake force distribution (EBD), dynamic stability and traction control systems, and front, side and curtain airbags.

A practical test: The Mazda SKYACTIV Experiment

With SKYACTIV having an ever-increasing prominence in its product lineup, Mazda Philippines initiated a practical test of the technology over two days and close to 500 kilometers of city and highway driving. Dubbed the Mazda SKYACTIV Experiment, it was conducted by the media using the Mazda6, the CX-5 FWD Pro, and the CX-5 AWD Sport.

Since SKYACTIV had been developed to provide real-world gains, certain measures were put in place to ensure that the experiment was conducted in real-world situations. “Veteran fuel-economy participants have their extensive list of tricks,” Tan notes. “But honestly, who drives with no air-conditioning given the choice? And no person in his right mind will cut off the engine and freewheel down a slope or on the highway in regular conditions!”

To simulate real-world driving, all nine test cars—three each of the above-mentioned SKYACTIV models—carried three media participants as well as a marshal to monitor the activities. Throughout the experiment, the marshals made certain that the drivers adhered to minimum and maximum road speeds, maintained the prescribed vehicle settings, and did not employ extreme economy-driving methods.

Shell FuelSave Gasoline was used as the standard fuel. Despite its 91-octane rating, it did not cause engine knocking and still extracted spritely performance from the SKYACTIV-G mills—a testament to the Mazda’s R&D efforts and engine-building prowess. Apart from meeting the SKYACTIV-G’s fuel requirements, the Shell FuelSave Gasoline formulation also contains detergents that clean and lubricate hard-to-reach internals to keep this advanced motor in prime firing condition.

The first day began with a top-up at Shell C5 near Mazda Pasig, the event’s take-off point. The route took participants for a morning drive around the busiest sections of Manila, Makati and Quezon City, with many stoplights along the way to challenge i-STOP. The feature got plenty of action on the road, shutting down the engine at every opportunity. The Mazda6 units’ i-ELOOP systems experienced a thorough workout as well. The city leg ended at Shell Balintawak, where the vehicles were fueled up again and fuel consumption was determined by dividing the distance traveled by the number of liters put in.

On the Subic-Clark-Tarlac Expressway (SCTEX) the following day, the agenda was to determine the most efficient highway running speed. After topping up the vehicles’ fuel tanks at Clark, the participants proceeded to cover the distance from Clark to the Hacienda Luisita exit then back to Clark via SCTEX at 60kph. At the end of the run, the vehicles were refilled with Shell FuelSave Gasoline to calculate for fuel consumption.

The 75-kilometer round trip was repeated two more times to determine the corresponding fuel-consumption figures when running at 80kph and at 100kph. During all the runs, the participants were advised to be as consistent as possible with their driving styles. They were also allowed to use the paddle shifters and cruise control to get better mileage.

The Mazda6 achieved the best combined city-highway fuel consumption, with the three units netting an average of 13.77km/L. The CX-5 FWD Pro was close behind with a mean fuel consumption of 13.42km/L, while the CX-5 AWD Sport got an average of 12.28km/L. The Mazda6’s and CX-5 AWD Sport’s figures are impressive given that both vehicles have bigger mills. It goes to show that the i-Eloop in the Mazda6 and the precise slip detection system in the CX-5 AWD Sport can counter the fuel-consumption penalties that normally come with larger-displacement engines.

Of note, the SCTEX runs revealed that 60kph is the most efficient speed for highway driving. At this speed, the vehicles posted the following mean highway figures: 23.59km/L for the Mazda6; 20.91km/L for the CX-5 FWD Pro; and 17.04km/L for the CX-5 AWD Sport. However, the corresponding 80kph figures show not very big fuel-economy payoffs: 17.99km/L for the Mazda6; 18.53km/L for the CX-5 FWD Sport; and 16.50km/L for the CX-5 AWD Sport. Running at 100kph produced the lowest highway numbers, but again, the differences were small: 16.47km/L for the Mazda6; 13.13km/L for the CX-5 FWD Sport; and 13.88km/L for the CX-5 AWD Sport.

“Of course it is good for the public to see the Mazda SKYACTIV Experiment’s results, but equally, we at Mazda are also very happy to see our efforts paying off,” Tan shares. “SKYACTIV represents a tremendous challenge undertaken by our company. We could have taken the easier way to achieving decent-enough results. However, by opting to go down the revolutionary road, we are now claiming even bigger gains in efficiency and performance, not just for ourselves, but for all those who buy Mazda vehicles as well.”