When an excessive demand for power causes both drive wheels to slip (for example, aquaplaning or accelerating on an uneven, snow-covered or icy road surface), the system reduces engine torque by decreasing the throttle valve aperture and thus the air flow. If, on the other hand, only one wheel slips (for example the wheel on the inside of the bend, after acceleration or a dynamic change in the load), this wheel is automatically braked without the driver having to touch the brake pedal. The effect is similar to that of a self-locking differential. This gets the Grande Punto out of any difficulties on surfaces where grip is poor.

ASR is engaged automatically every time the engine is started, but can be excluded by a pushbutton on the central console. ASR must be excluded when snow chains are fitted because in this case, in order to transmit torque to the ground, the wheel needs to be able to 'accumulate' the snow, with small slips that the ASR tends to avoid.

MSR (Motor Schleppmoment Regelung)

This system is also an integral part of ASR, which acts during sudden gear changes when changing down, returning torque to the engine, and preventing excessive traction on the drive wheels which can cause the car to lose stability, particularly when grip is poor.


Enjoyable to drive and to ride in

Fiat Grande Punto is an extremely enjoyable car to drive, thanks to the suspension that makes it handle very well, isolating it from the road, to a braking system that is powerful and effective in all situations, and to tyres that were studied specifically for the best comfort and maximum safety. And last but not least, "Dualdrive" electric power steering is available on all versions.


The new suspension on the Grande Punto

One of the goals set by the engineers who worked on the 'Grande Punto' project was to create a suspension system capable of offering performance comparable to that of upmarket cars. Devices that could guarantee easy, precise steering, excellent roadholding and the highest possible level of comfort for passengers. The choice went to two systems that have been tried and tested on other Fiat models, suitably modified and updated. The overall review of the geometries entailed the following changes:

• compared to the previous Fiat Punto, the tracks are wider and the tyres are larger (from 175/65 15" to 205/45 17");

• the geometry of the front suspension adopts lower links in a right-angled triangle, a solution that effectively separates the braking loads from the cornering loads to guarantee the best balance in all driving conditions. The new front geometry also allows the car's turning circle to be limited: on average it is about 10.6 metres, a value that leads its category and is very similar to that of the previous Punto, in spite of the larger wheels and longer wheelbase;

• the rear suspension is semi-independent and features interconnected wheels with a torsion axle designed to increase structural rigidity and to increase the flexibility of the suspension under load, by optimising the bushes between the rear axle and the bodyshell. The design for the new suspension also considered the shape of the buffer pads to improve the dynamic response when cornering;

• particular attention went into the design of any components related to comfort on the car, adopting technical solutions typical of higher segments. For example, the use of a 'dual-path' front strut mount on the front, and the position of the vertical damper at the rear; these changes made it possible to limit the effect of the vibration generated by the road surface, without altering the structural rigidity or losing steering accuracy;

• the size of the elastic bushes has been increased to filter out road roughness and to enhance comfort;

• on all versions, the dampers have been fitted with a 22 mm shaft to increase stability when cornering;

• the structural rigidity of the front crossbeam on which the suspension is anchored has been increased, in order to enhance vibrational and acoustic comfort;

• and finally, compared to the previous Punto, the track has been increased on both the front and the rear suspension, to adapt to the new model's larger external size and to improve stability: an average of 70 mm at the front and 75 mm at the rear.
  
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