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Selespeed: Formula One sequential gearbox
Q-System: Normal H-pattern manual shift or automatic shift
The all-new Alfa Romeo 156, which goes on sale on 26 February 1999 at the Melbourne International Motor Show, will be available with the choice of two of the most advanced and unique automatic gearboxes in the world.
The Alfa Romeo 156 Twin Spark is available with the optional Selespeed five speed automatic gearbox. This is a sequential automatic gearbox that is, quite literally, straight out of Formula One, both with its use of computer operated manual gearbox and clutch for maximum performance, and its steering wheel mounted button operated gear selection.
As well as being able to change gear in less than 0.7 of a second, it has a self-shifting mode that mimics a normal automatic gearbox and it even switches itself on the moment the driver opens the door so as to be ready for instant performance!
The Alfa Romeo 2.5 V6 arrives in Australia with the Q-System automatic gearbox as standard. This fully electronic four speed automatic gearbox presents the driver with two choices. In automatic mode it is a fully automatic gearbox with a choice of three operational settings, City, Sport and Ice.
Alternatively, by sliding the gear stick to the left the gearbox offers a conventional 'H' pattern manual gearshift, albeit without a clutch to operate.
This choice of conventional 'H' pattern gear operation, or fully automatic adaptive gear changing is a unique feature to the Alfa Romeo 156 and no other car offers a five speed sequential gearbox with steering wheel button operation.
"Once again Alfa Romeo is providing a new benchmark for performance and driving ability in Australia," says Newton Head, General Manager for Alfa Romeo in Australia.
"There is no other car, short of a $305,000 Ferrari, that offers a computer operated five speed gearbox the same as the Alfa Romeo 156 Selespeed and even it does not have the functionality of steering wheel mounted button-operated gear selection. The Q-System fitted to the V6-powered Alfa Romeo 156, meanwhile, offers the unique choice of fully automatic operation or a conventional 'H' pattern manual gearshift, providing the best of all worlds."
The Alfa Romeo 156 Selespeed
While other automatic gearboxes seek to mimic Formula One style operation - manual operation of a normal automatic gearbox by locking the gearbox in each gear - the Alfa Romeo 156 Selespeed is the real thing. It is directly derived from the Ferrari Formula One programme and offers exactly the same operation characteristics as the car driven by Michael Schumacher.
It is a five speed manual gearbox with a dry plate clutch. Gear changes are made by the computer system, which not only changes gear but also alters the fuel flow to the engine as the gears change. This means gear changes happen in 0.7 of a second and for maximum acceleration the driver simply keeps his foot flat to the floor and punches through the gears with the buttons on the steering wheel.
Selespeed: How it works and its advantages
From an engineering point of view, a conventional gearshift involves three stages. During the first stage, the clutch is opened to remove power from the wheels; during the second stage, with zero power, the driver selects and engages the gear and during the third stage the clutch closes to resume sending power to the wheels and engine speed begins to rise again.
The Selespeed gearbox implements these manoeuvres in a fully automatic manner. When the driver changes gear, there is no longer any requirement to release the accelerator pedal and depress the clutch; the electronic unit controls the gearbox and requests the clutch opening, it reduces the torque regardless of the accelerator position and it selects and engages the gears.
The Selespeed is to all intents and purposes a robotised manual gearbox. The decision over which speed to be engaged is left to the driver, but three actuators intervene to carry out the actions that are normally performed during conventional gear shifts. One controls the clutch, the other controls the engagement and the third controls the speed selection.
A fourth actuator is linked to the engine's electronic - or fly by wire - throttle. This device manages power delivery on the basis of requests received through the gearbox control system. During gearshifts Selespeed is in charge of the engine to ensure maximum performance and remove any risk of damage to any part of the drivetrain as the Selespeed system runs through its programs.
The major advantages of the Selespeed system are its speed of gearchange and lack of performance normally associated with automatic gearboxes.
Shift time is measured from the beginning of the power removal to the end of the re-application of the power. With a conventional manual gearbox, this operation takes a minimum of between one and one and a half seconds with even the most expert of drivers. In normal driving mode, Selespeed takes approximately the same amount of time, for driving comfort. However, when the gearbox is used in 'Sport' mode, which is engaged simply by pressing the accelerator through more than 60 per cent of its travel and the engine speed is above 5000 rpm, gearshifts are accomplished in less than 0.7 of a second.
The Selespeed gearbox makes it possible to push performance driving to the edge of the envelope without altering engine performance, which means that unlike any other conventional automatic gearbox, there is no blunting of either acceleration or top speed with the Selespeed gearbox.
With gear selection operated by two buttons on the steering wheel, the driver is left free to concentrate on steering and braking, which are more strong points of the Alfa Romeo 156. And if the driver forgets to change gear under full-bore acceleration, the Selespeed system will change gear automatically.
Sporty and performance orientated when needed, Selespeed is also comfortable and easy to drive. The Selespeed can work in two modes: semiautomatic and automatic. In the first the driver changes the gears manually using the buttons on the steering wheel and the system automatically operates the clutch, selects the gears, engages them and operates the engine during shifts. In the second case, when the city button is pressed, shift controls and decisions over the type of gear to be engaged are delegated to the Selespeed and the driver is left free to enjoy a relaxed drive that is particularly useful in city driving conditions.
Selespeed: How it is used to drive the Alfa Romeo 156
The Alfa Romeo 156 Selespeed is a very easy car to drive. To start the car moving, simply depress the brake pedal and engage first, second (in slippery conditions) or reverse gears by using the gear stick, as the buttons on the steering wheel do not become active until the car is doing more than 10 kmh.
With a gear engaged, simply release the foot brake, press the accelerator and the Selespeed moves off. Once the car is doing more than 10 kmh, either the gear stick or the steering wheel buttons can be used to change gears. If both controls are accidentally used at the same time, the gearstick has priority.
As mentioned above, there is no requirement to ease off on the accelerator during up-shifts or to bring the revs up on down shifts: this is handled automatically by the Selespeed system.
The built-in safety system means that the drive train is fully protected from gearchanges that would damage it. In other words if the engine and road speeds in the gear chosen are not compatible, Selespeed will not change the gear and a visual warning will be presented on the dashboard gear indicator. The system will not leave the driver stranded in neutral, though, as it will select a suitable gear for the road and engine speed.
In emergency braking manoeuvers, the Selespeed system automatically changes down through the gears, providing additional braking force and balance for the car under braking. Likewise, the car can detect when it is descending a hill and will shift down through the gears for engine braking and increased balance.
Going down through the gearbox is just as easy as accelerating and Selespeed removes the need for heel and toeing as each time it engages a lower gear it raises the engine speed to match the road speed in the new gear automatically.
As the car comes to a halt, the clutch automatically disengages preventing the car from stalling. If the car does not come to a complete halt, the system automatically selects the ideal gear for moving off at any given speed.
To disengage the system, press the brake pedal and move the gear lever to one side. For safety reasons, the system will not engage neutral at speeds over 40 kmh.
For safe parking, the 156 Selespeed must be left in a gear. If this not done, a buzzer reminds the driver that he must leave the car in a gear. When the engine is started, Selespeed puts the car in neutral before activating the starter motor.
Once the engine has been switched off, Selespeed deactivates itself, but not before it has run a self-diagnostic program and stored the data from that programme and from the just completed trip in its memory.
Selespeed and safety
The Alfa Romeo Selespeed boasts a series of features designed to prevent the driver making incorrect decisions that could create dangerous situations or damage the system. Selespeed is, therefore, able to ensure maximum safety in all situations..
These features include:
The engine may only be started with a gear engaged or in neutral. In any case when the brake is released and the accelerator pressed, the system automatically searches for neutral.
The brake pedal must be depressed to engage a gear when the car is at standstill. This prevents the car moving off by accident.
When the car is stationary only three gears suited for moving off may be engaged, first, second and reverse.
When the car is traveling at less than 10 kmh, only the gearshift may be used to engage gears, the steering wheel buttons are disabled so that they cannot be used accidentally in low speed manoeuvering.
If the buttons and gearstick are operated simultaneously, the gearstick has priority.
Reverse cannot be engaged if the car is moving forwards or backwards.
Gearchanges are not permitted if they take the engine outside its operational range.
If the driver passes the redline, the engine will change gear of its own accord.
Neutral is inhibited at speeds above 40 kmh.
The car moves into neutral and a buzzer sounds when the driver's door is opened with the engine running for more then a second; if the accelerator and brake are not depressed within a minute of a gear being selected; if the oil pressure is too low to safely operate the gearbox.
City mode is cancelled as soon as the gear stick or buttons on the steering wheel are touched.
A warning light system on the dashboard tells the driver which gear the car is in and the operational status of the system
The Selespeed system runs full diagnostic checks on itself on start up and close down and recalls all intermittent faults for checking by service technicians. If the system is faulty, it first locks in city mode and then, if the fault or problem becomes worse, closes down systems to protect the car and enable the driver to reach a service centre.
Selespeed: How it works
1) Gearbox electronic management unit
2) Selespeed clutch-gearshift acuator unit
3) Engine electronic management unit
4) Throttle with electronic accelerator
5) Gear engaged indicator on facia
6) Down button for shifting down through gears |
