2013 Lexus GS Review Part One: Tackling the Technical


Lexus GS Chassis

Two weeks ago, I was invited to test drive the all-new 2013 Lexus GS in Dana Point, California. This is the first part of my review.

In a presentation I attended just prior to getting behind the wheel of the new Lexus GS, Chief Engineer Yoshihiko Kanamori, outlined the four key objectives for the car’s development team:

  1. Create an emotional driving experience.
  2. Move Lexus design in a new direction.
  3. Advance Lexus leadership in hybrid technology.
  4. Provide the best packaging in the mid-size luxury class.

It turns out that these four goals make up the essential story of the new GS, with each deserving special attention. Today, let’s start with the technical component of Kanamori-san’s primary target — making the fourth-generation GS more fun to drive.

“To provide an emotional driving experience, I believe a car must provide agility, acceleration and the braking a driver expects,” Kanamori-san told us, “For some, it may mean driving quickly over a challenging road, and for others it may be cruising down the highway, but for many drivers, it means both.”

The very first step taken by GS engineers was stiffening the body structure to to improve overall stability and control.

Lexus GS High-Strength Steel & Laser Welding

“Chassis tuning starts with a stout frame, which benefits extensively these days from computer-aided analysis and engineering,” Paul Williamsen, National Manager of Lexus College, explained. “As a result of that, the engineers made some decisions to dramatically increase the use of high-strength steel, and using much more laser welding are certain key high stress body areas.”

Lexus GS High-Strength Steel Reinforcements

All this work at stiffening the chassis lead to some serious improvements, with rigidity up 14% over the previous generation GS — and most importantly, almost no increase in overall weight.

In order to balance the extra mass, Lexus engineers turned to reducing weight in other ways, including the use of hot-pressed steel, a metal so strong that it must be heated to high temperatures with an electric current before it can be stamped. This was used for the B-pillar and the roof side-rails, and helped to achieve extreme high strength with low weight — here’s a breakdown of the metals used:

Lexus GS Exterior Weight Reduction

This weight reduction extended into the cabin and the interior materials as well:

Lexus GS Interior Weight Reduction

The next area GS engineers focused on was the suspension, which remains a double-wishbone setup in the front and a multi-link setup in the rear, but with several key improvements — most notably in the use of aluminum to reduce weight. The rear springs were also moved to allow for more trunk space, with the actual links reconfigured to make room for the F Sport package’s rear-wheel steering.

The GS Adaptive Variable Suspension (AVS) was also redesigned, moving from the conventional setup that has sensors in each corner of the vehicle to an all-new system that calculates dampening based on overall movement:

Lexus GS Adaptive Variable Suspension

This new system allows the AVS to control all four wheels simultaneously, improving ride quality at low speeds and stability at high speed — very important when it comes to balancing performance and comfort.

Also new to the 2013 GS is Lexus Dynamic Handling (LDH), a GS F Sport option that combines two technologies — Variable Gear Ratio Steering, which adjusts the steering based on speed (more responsive at low speeds, less so when travelling at high speed), and Dynamic Rear Steering (DRS), which turns the rear wheels up to two degrees in both directions. The DRS system also adjusts itself based on the speed of the GS — at higher speeds, the rear wheels turn in the same direction as the front wheels for improved stability, but at lower speeds, the rear wheels turn in the opposite direction for better handling.

All of these systems can be controlled by the driver by using the Drive Mode Select dial located in the center console:

Lexus GS Drive Mode Select

With Normal as the baseline, the remaining three modes affect the driving performance in different ways:

  • ECO Mode is focused on fuel economy, smoothing out any abrupt variations in the throttle and placing tighter restrictions on the air conditioner.
  • SPORT S Mode increases throttle response, quickens transmission shifts, and enables downshift throttle blips.
  • SPORT S+ Mode, which is available to GS models equipped with AVS, adjusts the suspension, electric power steering, VGRS and the VDIM settings.

Not all the improvements were highly technical in nature — simple sound also played a key role, with GS engineers employing a Intake Sound Creator to pipe engine “noise” into the cabin, similar to the technique used in the LFA:

Lexus GS Intake Sound Creator

Lastly, adjustments were also made to the muffler, simplifying the flow to create a sportier exhaust note:

Lexus GS Exhausts

In a way, it’s ironic that so much technical work goes into creating a more “emotional driving experience”, but it also reflects a certain pattern I see developing around the new GS. There’s this sense of balance — excitement and comfort, technology and passion, performance and luxury, form and function — and it’s a feeling that only grows throughout the day of driving.

Tomorrow: Moving the Lexus design forward.

Comments


  • http://www.facebook.com/LexusandThePursuit WorldofLuxury

    OMG! SWEET STUFF! THANKS KREW!

  • http://twitter.com/BlackDynamiteNY BlackDynamiteOnline

    I thought I was the only one Lexus trusted with this R&D information……..
    BD

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    In my opinion it should be more strong!

  • F1

    This is simply overwhelming.. Lexus is all about the detail

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    that is a great post! thank you for sharing))))

  • Rarmour

    Most of this technology will never be recognized by the average Lexus owner. They just want a quiet, comfortable riding car, with decent gas mileage and dependability.  The ride control knob will never get used.

  • http://www.facebook.com/people/Sebastien-Kroetsch/550680597 Sebastien Kroetsch

    It’s nice to have a look at the training we’re getting on it in a few weeks from now ;) Thanks Krew.

  • http://www.facebook.com/RDS.Alphard Yong Thian Ding

    I would agree on this .

  • http://www.facebook.com/RDS.Alphard Yong Thian Ding

    This R&D … shouldn’t just appear on Lexus , but should also some other car , maybe FT86 .

  • John Ryan3

    This is my 3rd GS and is nothing like any other.  As far as the “ride control knob” It changes the feel and power so much I find myself using it all of the time.  Lexus went all out on this one and let me tell you, it’s a fun car to drive.

  • craig ross

    nice to here that.. i just ordered a 2013 lexus gs 350 awd f-sport model…

  • richard

    I use mine all the time. It’s like a different car on the Eco, normal,and s+ settings. I can’t tell much diff.nin S mode