Front suspension

Fiat Grande Punto has independent suspension on which the damper and the spring act as both damping, elastic elements and as structural, cinematic elements. The main components of this structural system are the twin-shell pressed metal wishbones (with the patented 'butterfly' layout) made of pressed sheet metal rather than cast iron as on the previous model, with a significant weight saving; and the adoption of bushes with a larger amount of rubber than on the Punto, to enhance comfort (absorbing small bumps) without detracting from the excellent roadholding and stability on corners.

The new model also introduces a number of really interesting ideas:

• an extremely rigid front suspension crossbeam with a transverse linking strap close to the front link attachments;

• reinforced uprights for better roadholding when cornering;

• 'dual-path' double front strut mounts to filter the vibration from the road better, while ensuring a high level of structural rigidity which enhances steering precision;

• anti-roll bar with small con rods to anchor it to the dampers, which enhances efficiency and ensures prompt dynamic response when cornering;

• coil springs that adopt the 'side-load' technique to optimise the thrust axis, so as to reduce the tangential loads on the damper shaft and thus any internal friction (system hysteresis), so that surface roughness can be absorbed better;

• all the versions fit dual rate telescopic hydraulic dampers with a shaft diameter of 22 mm, to increase lateral rigidity and improve cornering. They also fit new improved valve units that optimise vibration damping;

• and finally, the upper strut attachment to the bodyshell has been made stiffer, to improve acoustic and vibrational comfort.
  
  
  Rear suspension
  
  This is of the semi-independent type, with wheels connected by a rear torsion axle, a layout that has been optimised since the previous Punto. Starting with the bodyshell attachments which have been widened and optimised in terms of the torsion element, making it possible to increase structural rigidity in spite of the lower weight.
  
  
  What is more, the particular shape of the torsion element (the thickness of which varies with the version) has made it possible to achieve optimal anti-roll values, even without an anti-roll bar.
  
  
  That is not all. The vertical layout of the dampers, which are attached to the bodyshell inside the wheelarch, has enhanced the filtering of surface roughness, which improves acoustic comfort in the passenger compartment. The rear axle structure is made up of lateral links pressed in two half-shells welded to a lateral torsion element which has a cylindrical butt join on the links.
  
  
  And finally, the larger rear axle anchorage bushes support a higher longitudinal flexibility of the suspension under load, while the particular shape of the buffer pads ensures a prompt dynamic response when cornering.
  
  
  
  Braking system and large tyres
  
  In line with its high active safety targets, the Grande Punto is equipped with highly efficient, extremely sensitive braking systems. First of all the braking system is backed up by the most sophisticated electronic and mechanical aids - ABS with EBD, ESP complete with ASR/MSR, Hill-holder, HBA (with ESP) - and it is of the servo-assisted hydraulic type, with two independent, cross-over circuits (each circuit governs a front wheel and the diagonally opposite rear wheel) to guarantee braking and stability even if one circuit should fail.
  
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