Major dynamics enhancements for the FG Falcon (to be released in May) over the BF2 include:
- An all-new lightweight Virtual Pivot Control Link front suspension;
- All-new forward mounted steering gear with variable ratio and Y-shaped rack;
- Significant modifications to the Control Blade Independent Rear Suspension across all sedans;
- Monotube shock absorbers across all sedans and most Ute variants;
Virtual Pivot Control Link front suspension The all-new Virtual Pivot Control Link front suspension is a key component of the Falcon chassis system and introduces a set-up similar to that which has already proved so effective and popular on the Ford Territory.
The width of both the front and rear suspension tracks has been increased, along with a corresponding increase in wheelbase, for improved stability.
Although similar to the Territory front suspension, the springs, dampers, anti-roll bars, suspension bushes and suspension geometry have all been optimised for Falcon to deliver the perfect balance of ride, handling and steering best suited to a sedan on Australian roads.
Incorporating a highly sophisticated double wishbone design with two lower ball joints that is usually seen on far more expensive vehicles, the new front suspension provides a weight saving of 22 kilograms over the BF Falcon through the use of aluminium and high strength steel.
It also provides for reduced King Pin offset packaging and allows the introduction of a forward mounted steering rack.
In comparison to other locally-built rear-wheel-drive sedans that use a virtual pivot control link with a McPherson strut, the FG Falcon system uses a virtual pivot control lower link and an upper A-arm, which results in better camber when cornering, leading to improved tyre contact with the road and increased assurance for the driver.
The new suspension system incorporates two ball joints that connect the separate lower arms to the suspension knuckle. These two separate lower links define a virtual pivot of the lower arm, which allows the suspension to behave as though the lower pivot point is at the intersection of the two arms.
The virtual pivot point is further outboard than can be achieved by a conventional suspension system, leading to a reduction in the King Pin Axis offset, which thereby reduces the ability for wheel disturbances from wheel balance and tyre non-uniformities to disturb the driver through the steering wheel.
Similarly, the negative scrub radius that is generated by the new front suspension allows the wheel to generate some self-correcting steering torque while braking, which improves braking stability on mixed surfaces and provides better control under adverse conditions.
Steering "One of the greatest benefits of Falcon's new front suspension system is that it has allowed us to package a forward mounted steering rack," said de Vlugt.
"In order to achieve the optimum balance of steering precision, handling stability and high speed controllability, we needed to deliver an increased level of front axle compliance understeer, and this can be best achieved with a forward mounted steering rack.
"For drivers of the new FG Falcon, this will translate to very confident control of their vehicle in busy traffic and through narrow roadways and road works. In addition to excellent manoeuvrability, the new virtual pivot control link front suspension, in combination with the new steering gear geometry, also contributes to reduced tyre wear."
The new steering gear introduces variable ratio technology, which provides the optimum sensitivity at low speeds and a relaxing drive at higher speeds. This results in a reduction in the number of turns lock-to-lock, without being too sensitive during straight ahead driving.
FG Falcon combines an 11.0 metre turning circle with 2.6 turns lock-to-lock steering.
This direct steering is mostly felt at low speeds where significant steering wheel angles are used, however, the variable ratio steering allows for a less direct steering ratio when the steering is "on centre" or near the straight ahead position.
The FG Falcon is also the first Australian-built vehicle to incorporate a Y-shaped steering rack, which was invented by Bishop Steering Technology in Australia.
The Y-shaped steering rack significantly improves stiffness and smoothness of motion and operation, eliminating the knobbly, discontinuous feel that is normally prevalent in vehicles with a variable ratio steering gear, which is generated by rolling torque around the steering gear axis whenever the steering wheel is turned.
Enhancements to steering for the FG Falcon also include two new power-assisted steering calibrations to optimise steering feel across all models.
A new ergonomically designed steering wheel for base and luxury models also contributes to a more relaxed driving experience, while a sports steering wheel for the performance models provides for a more confident grip on the steering wheel during enthusiastic driving.
"The combination of steering advances we have introduced with the FG Falcon ensures we have rebalanced the level of vehicle response to steering inputs over the speed range," said de Vlugt.
"At low speeds the new Falcon offers high levels of response thanks to the variable ratio steering rack, while at higher speeds it responds less, making it less 'nervous' during highway driving."
Control Blade IRS
The FG Falcon continues with the acclaimed Control Blade IRS architecture that was first introduced on the BA Falcon in 2002. However, all suspension springs, dampers and the anti-roll bar links have been significantly revised to match the introduction of the new front suspension.
One important change is an increased roll centre height to match the new front suspension, which reduces in-corner roll and improves straight line stability, along with a revised toe-angle that provides improved steering feel and vehicle stability.
Other rear suspension advances include new "point three" bushings, which improve NVH and deliver a quieter drive without loss of steering or handling performance, along with a small increase in track width.
Revised roll steer and the introduction of a new rear anti-roll bar connection link both also combine to deliver greater steering efficiency and precision.
"Since 2002, Falcon's IRS has been recognised as one of the best in its class, particularly compared to other Australian-made vehicles," said de Vlugt.
"We've been able to continue developing and enhancing that system and match it to the new Virtual Pivot Control Link front suspension without losing any of the technical advantages that have led to an enjoyable and confident driving experience for Falcon customers.
"The core system was engineered to stand the test of time and the engineering changes we've made now enhance that."
Monotube shock absorbers The introduction of monotube shock absorbers front and rear on all Falcon sedans and most Utes will further enhance the dynamics capability of the FG Falcon through better body control and handling. Improved plushness and vibration absorption will also contribute to a more comfortable ride without any perceived 'floatiness'.
Monotube shock absorbers have one tube with a gas cup to separate the gas and oil, and accommodate the oil displaced by the rod entering the working area. In contrast, traditional twin tube shocks have no physical separation of the oil and gas in the damper and operate by transferring the oil from the pressure chamber via a base valve as the shock rod displaces.
The larger piston area of the monotube shock reduces hydraulic pressure, which improves sensitivity and control, especially on short strokes and reversals.
Significantly higher internal gas pressure of 18 bar, in lieu of 4 bar with twin tubes, allows the damper to build controlling forces faster and nearly eliminates cavitation or foaming during normal operation. This guarantees consistent ride feel and control as well as markedly improving performance.
In addition, the higher operating temperature capability (160?C) of monotube shock absorbers ensures control in strenuous duty cycles such as over corrugated and gravel roads.
Monotubes also dissipate heat more quickly and can absorb more energy for longer periods of time than twin tubes in equivalent conditions, which delivers increased robustness under all driving conditions.
"By introducing monotube shock absorbers into Falcon we are able to improve its road holding capability even further," said de Vlugt.
"Drivers will notice appreciably enhanced handling and steering without any loss of ride performance."