Subaru engineer details Forester's furtherance

SUBARU’S just launched sixth generation Forester may appear to be an evolution of the outgoing model.

And indeed, while it shares a petrol engine and driveline with its predecessor, the arrival of Subaru’s Strong Hybrid technology – and several other important changes – elevate the model’s safety, ride/handling balance, and overall refinement considerably.

Speaking with GoAuto at the Australasian launch of the all-new Subaru Forester in Christchurch, New Zealand this week, Subaru Forester project manager Takuya Fujii said the model was designed to adhere to the DNA of the Forester family, while at the same time differentiating itself from segment rivals.

“I think it (the new Forester) fits perfectly with the demands of our customers,” he said.

“Our emphasis has always been on driving performance and safety – highly responsive handling and robust drivability across all conditions empower every driver with precise and confident control.

“(Further), technology such as Eyesight and our new Super Global Platform are just a few of the items on the list that will continue to set the standard for Subaru products moving forward.”

Mr Fujii explained how the Subaru engineering team had worked to evolve the Forester formula while retaining the features and functionality owners desire, highlighting platform and technology improvements, upgraded seating, and the benefits of Subaru’s Strong Hybrid powertrain.

“We have made some major improvements to body rigidity and stability, handling, control, and the reduction of noise and vibration,” he continued.

“Our new Super Global Platform increases torsional rigidity by 10 per cent when compared with the previous model. We adopted a full inner-frame construction method and increased the amount of structural adhesive by more than three times.

“Additionally, the seats are now directly installed on the frame, instead of using a bracket between the seat and the body, enhancing stability for the driver. Coupled with overall stronger body construction, the design allows the driver to always feel safer and more connected to the vehicle.”

Aerodynamic improvements aimed at improving fuel economy and reducing drag were also a top priority for Mr Fujii’s team.

He said the high ground clearance and boxy shape of the Forester provide challenges that are sometimes difficult to address, but said “a completely redesigned structure and exterior design (have helped to) reduce turbulence and maintain good control regardless of road conditions”.

Other changes aimed at improving stability of the all-new Forester include a more costly, but more agile dual pinion electric assisted steering system where the drive motor is installed on the rack, and not on the column.

Mr Fujii said the system “minimises unnecessary resistance” and “gives the driver more control over the vehicle”.

Importantly, the new Super Global Platform also delivers benefits where noise, vibration, and harshness (NVH) are concerned.

Mr Fujii told GoAuto he and his team spent considerable time and resources in ensuring “interior comfort levels were improved, and driver stress minimised”, adding “thicker and wider” noise suppression materials and coating components that could transmit noise and vibration with a “high-damping mastic material”.

“A high damping mask has been applied in several key areas to reduce noise penetration wherever possible,” he detailed.

Thicker front door glass aims to improve the clarity of conversations in the cabin, while insulative material in the toe board, firewall, dashboard, and transmission tunnel reduce A-weighted sound pressure by between 1 and 3dB in the front seats and between 4 and 6dB in the rear.

Adding to a greater sense of comfort and support, the seat design is improved to offer increased lower back support, Subaru engineers taking a “scientific approach on designing the structure of the human body in order to fit (the seat) more firmly around drivers of all sizes and ages”.

While details of Subaru’s Super Hybrid system – co-developed with Toyota and including a Toyota-sourced battery and traction motor – are already well documented, Mr Fujii explained that the powertrain aims to be different from others in the market by offering improved drivability and peak performance, in addition to better fuel efficiency.

“Of course, fuel efficiency is a major focus, but it is definitely not the only thing we focused on,” he explained.

“We needed to look back on our DNA and talk with our customers to find out what they really want from the hybrid Forester. (In doing so) we were able to achieve a very good balance of performance and economy, while also ensuring the system’s durability off-road.

“Acceleration has been improved. In fact, the hybrid is stronger and more responsive in terms of acceleration than the petrol model. The electric motor not only assists in providing a flat, even torque curve, but also better low-speed response, which is crucial in both on- and off-road driving.”

Off-road, the new Forester offers class-leading ground clearance and geometry. Underbody clearance is listed at 220mm (just 4mm less than the Ford Ranger XL ute) while approach, ramp-over, and departure angles are listed at 19.0 degrees, 19.3 degrees, and 24.7 degrees (SAE) respectively.

Subaru’s dual-mode X Mode all-wheel drive system continues to feature, offering cross-axle torque vectoring by brake, and alternate traction modes for improved grip in mud, snow, and sand.

Despite the added ride height and off-road prowess, Mr Fujii said passenger comfort will match or better that of a typical passenger car.

His engineering team tuned the coil springs, bushings, and dampers to reduce those movements resulting in passenger head toss (an undesirable outcome of higher riding vehicles and common in many SUVs and utility vehicles) and oscillating upper body movements, improving comfort – and potentially reducing motion sickness.

It’s the smaller, often unseen details Mr Fujii and his team believe will see the model become another successful chapter in the continuing Forester story.

With city and country drivers at its heart, the Forester is certain to appeal to a broad range of customers right across the country, feeling new – but also purposefully familiar – all at the same time.