This is a strut tower bar with a completely new concept – splitting an aluminum tower bar in the center and connecting the two pieces with pillow ball joints. As the left and right pieces are flexibly connected, the bar can moderately handle longitudinal forces such as from gaps on the road to maintain ride comfort while strongly holding against lateral forces during cornering. As a result, not only cornering performance but also straight-line stability and ride comfort is improved to enhance the comprehensive performance level of the car.
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FLEXIBLE TOWER BAR
Introducing the FLEXIBLE TOWER BAR that has been developed based on a totally new idea. With one installed in their car, anyone can be good at driving on any type of road.
What is the STI Flexible Tower Bar?
STI believes that it is important to improve road-holding abilities of wheels in order to allow the driver to control the car much like an extension of their own body. The Flexible Tower Bar is an STI original product which has been developed to achieve such a goal. Unlike a conventional rigid bar, the Flexible Tower Bar is split and joined with pillow ball joints in the center to be longitudinally mobile while helping laterally stiffen the body of the car.
Different from a rigid bar which is designed just to increase rigidity of the body of a car, the concept behind this bar is to constantly enhance traction of the wheels by strongly holding in a transverse direction at the same time as moderately handling the impact from the ground, in order to realize a ‘flexible yet elegant driving feel’.
As a result, responsiveness at the time of steering improves without compromising comfort, which allows the driver to actually feel that the car can turn as intended, and when they want to go straight, it provides a stable drive without too much impact from uneven road surfaces. As described, this product will further deepen your pleasure of driving.
A car needs flexibility? STI’s idea defies conventional thinking.
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In car development, it is generally believed that a stiff body provides good driving performance and a soft body does not. STI was no exception by always thinking in which part of the body we should increase rigidity. However increased rigidity improved one area but inevitably had a negative impact on another. Modern car bodies are strengthened to improve collision safety in the first place. Therefore we stopped following the book for once and shifted away from pursuing rigidity. As we decided to add flexibility which is rather the opposite of stiffness, this Flexible Tower Bar, which further brushes up the great performance of a SUBARU while retaining collision safety, was brought to life.
The power of the Flexible Tower Bar has been proven at the Nürburgring 24-Hour Race
The Nürburgring in Germany features a 20.832 km track with a 300m change in elevation from its lowest to highest point and 172 corners. As well as an undulating track surface known for being slippery, and blind corners representing a large percentage of its design, the track includes all the elements of a public road. STI, with the SUBARU WRX STI equipped with the Flexible Tower Bar, has been competing in the tough 24-hour long race on this track. As the Flexible Tower Bar enhances responsiveness of the car and stabilizes it on straights and corners, STI’s four drivers can feel secure behind the wheel even in the ever-changing weather of the Nürburgring. Hideki Yamauchi, one of the drivers says, “The Flexible Tower Bar makes a difference in the feeling of security. As it improves responsiveness, as well as road-following ability and comfort, the car is easier to drive”.
STI has won in the SP3-T class in the Nürburgring 24-Hour Race four times.
Test Results
The Flexible Tower Bar offers you…
Responsiveness of the car improves, which delivers spontaneous proper steering.
As steering requires less attention from a driver, they can be more attentive to the surrounding environment such as pedestrians crossing the road and cars running side by side, and thus feel at ease and relaxed to drive.
The Flexible Tower Bar exerts its effect even at low speeds such as when a car is in reverse. It allows a driver to eliminate unnecessary steering maneuvers because they can control the car exactly as they intend to do. As a result, they can calmly comprehend the environment including the movement of their own car and position of other vehicles.
Furthermore it stabilizes the car when running, so passengers do not have to strain their body muscles and feet to support themselves against jolting, and the risk of carsickness is reduced. Therefore not only the driver but also all passengers in the car can be more comfortable and enjoy the ride.
How does it perform on winding roads?
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On roads with a series of blind curves, drivers can get tired as they have to also pay attention to oncoming vehicles in addition to the behavior of their own car. With the Flexible Tower Bar, your car will turn as you wish with stability so you can avoid turning steering wheel too much and entering into the opposite lane or feeling a chill when you are late to turn the steering wheel back.
What is the advantage when driving a long distance on a highway?
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Have you ever had the experience of feeling insecure when a car wobbles when accelerating at a highway interchange? With the STI Flexible Tower Bar fitted to the car, drivers can feel secure behind the wheel on a highway as movement of the car is suppressed and the wheels tightly hold the road surface. In addition, as the certainty of the movement of the car increases, drivers can feel that the car is definitely running straight, which allows drivers to firmly check the rear to make a lane change with a sense of security.
How does it handle rough terrains such as mountain paths and snowy roads?
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On an unpaved mountain path with a number of bumps or on a slippery snow-covered road, drivers spontaneously repeat steering adjustments to deal with the small bounces and skidding that a car can face from a variety of road surfaces. These efforts in driving cause fatigue to build up for the driver. If you install the Flexible Tower Bar, you will be able to enjoy safe driving without fatigue because you can clearly feel the changes in road conditions though the car and you consequently need less adjustment in steering.
