Thanks to Alfa Romeo’s innovative ‘Q2’ system (launched in Europe today on selected 147 and GT models) you can now have the best of both worlds – the convenience and safety of front-wheel drive coupled with the enjoyment and control of a rear-wheel drive car. In short, Q2 stands for Alfa Romeo’s self-locking front differential system and it provides many of the advantages typical of four-wheel drive, but at a significantly lower cost and weight.
The system is now available exclusively with the 110 kW JTD MultiJet engine on the Alfa GT and Alfa 147, but will subsequently be extended to other models in the Alfa Romeo range. It is a step forward that reflects the current state of the art of turbodiesel technology which, since 1997, the year that the Alfa 156 JTD was launched (the first car to adopt Common Rail technology), has seen a considerable increase in torque delivery to the wheels even on compact cars. Alfa Romeo has developed the sophisticated ‘Q2’ system to guarantee maximum control and traction in all driving conditions.
In addition to the new transmission, the Alfa 147 ‘Q2’ is also identified externally by a number of stylistic details: satin finish bealing in the lower grille, chromed mirror housings, special 17” alloys, a rear spoiler, chromed exhaust terminal, lower stance and the ‘Q2’ logo at the rear. Inside, this version has a particularly sporty outfit underlined by instruments with red scale background and white lighting, leather upholstery with red stitching on the steering wheel, gear lever and hand brake gaiters, grey anthracite trims on the steering wheel and central console, special ‘Q2’ heel-high strips and aluminium pedals. The equipment of the Alfa 147 ‘Q2’ is completed by a Bose® Hi-Fi system – this is on top of normal 147 fare which includes radio controls on the steering wheel, cruise control, the VDC system and 6 airbags.
The Alfa GT ‘Q2’ version, on the other hand, has specific 18” rims, dual chromed exhaust terminals, satin finish grille with new beading, chromed mirror housings, lowered stance and the ‘Q2’ logo on the tailgate. The styling of the interior underlines this version’s sporty character: an instrument panel with a red background and white lighting, black leather seats with red stitching and the Alfa Romeo logo, the steering wheel, gear lever and handbrake gaiters in black leather with red stitching, special ‘Q2’ heel-high strips, grey anthracite facia trims and aluminium pedals. And finally a Bose® Hi-Fi system with sub-woofer completes the standard kit.
The introduction of the ‘Q2’ versions extends the popularity of two models, which are not only achieving their set goals but exceeding every expectation. For example, in under three years, the Alfa GT has acquired over 55,000 customers in Europe. Since 2000, more than 500,000 147s have been bought by European motorists. And we cannot overlook the accolades from the trade press which, to date, has awarded the 147 a total of 32 prizes, acknowledging the car’s ability to express a new concept of sportiness in which elegance, comfort, safety and refined technology converge. Prizes from the critics include: the title of ‘Car of the Year 2001’, ‘Volante d’Oro’, ‘Trophées du design 2000’, and ‘Auto importado del Año en Brasil 2002’; while those awarded by readers include: ‘Auto Europa’ in 2001, and ‘L’auto che preferisco’ in 2001, 2003, 2004 and 2005.
Fiat Auto SA is currently assessing the feasibility of augmenting the 147 and GT ranges with the new Q2.
How does the Alfa ‘Q2’ system work?
The main element of the ‘Q2’ system is a limited slip differential, of the Torsen mechanical type. This differential splits torque between the front drive wheels dynamically and constantly, according to driving conditions and the road surface. Combined with the exclusive double wishbone front suspension, the system allows very effective fine tuning of the car.
Alfa Romeo started from the excellent reputation that front-wheel drive enjoys with customers (in fact it is the layout chosen by the majority of car-makers). Suffice it to say that, in addition to the overall benefits of this type of architecture (weight, roominess, etc.), in extreme conditions, the understeer typical of front-wheel drive enables the driver to respond more intuitively to the car’s reactions: this gives the impression that front-wheel drive is more ‘responsive’ than rear-wheel drive.
To highlight these benefits, Alfa Romeo has developed the ‘Q2’ system which embodies all the strengths of front-wheel drive, significantly increasing roadholding, traction and stability on the release, while attenuating understeer on acceleration, the intervention of the electronic control systems and steering wheel vibration.
The two practical examples below highlight the technical potential of the ‘Q2’ system.
Case no. 1: when the car corners
Taking a corner when grip is poor (wet road, snow, mud, etc.) or with a sporty driving style, grip is often lost on the inside wheel. When the transfer of the lateral load takes weight off the suspension, torque on the inside wheel is reduced, and a conventional differential (which splits the same torque value between both wheels) transfers an equal amount of torque to the outside wheel, but this is insufficient for good traction. In this situation the car can respond in two different ways, depending on the equipment mounted. On a model without ASR-VDC, the perceived result is the slipping of the inside wheel, a loss of control of the car (strong understeer) and a loss of acceleration coming out of the bend. If, on the other hand, the car is equipped with ASR-VDC, the intervention of the driving assistance systems takes power from the engine, acting on the throttle valve and the braking system, so that it becomes impossible to modulate the accelerator, producing the unpleasant sensation of a drop in power. In both cases, the result is that as the car comes out of the bend, the driver has the feeling that it is ‘stationary’.
What happens when the ‘Q2’ system is present?
When the inside wheel starts to lose grip, torque is partially transferred to the outside wheel, producing less understeer, greater stability, and increasing cornering speed.
The improved mechanical efficiency of the ‘Q2’ transmission delays the intervention of the vehicle control systems, guaranteeing better traction as the car exits the bend, which makes driving more enjoyable and maintains complete control of the vehicle.
Case no. 2: surfaces with poor grip
On surfaces with poor grip, it is quite common for the drive wheels to have different degrees of grip. For example, grip under the two wheels can differ on snow-covered or wet roads.
In these conditions, starting off or accelerating sharply could cause the wheels to slip, generating critical friction conditions, a strong reaction on the steering wheel, and inadequate take-off, making it necessary to correct the steering-wheel continuously to maintain the trajectory.
What happens when the ‘Q2’ system is present?
The negative effects are attenuated by the gradual transfer of torque to the wheel that can exploit the best friction coefficient, simplifying a hill start, for example, and making driving on all roads with changing surface conditions safer and more comfortable.
