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Rally Argentina Michelin preview

2001 World Rally Championship Round 5: Rally Argentina (May 3rd-6th 2001) Without water, please! Each year, as the first smooth gravel round of the season, the Rally of Portugal tends to serve as a pointer to the relative potential of the main...

2001 World Rally Championship
Round 5: Rally Argentina (May 3rd-6th 2001)

Without water, please! Each year, as the first smooth gravel round of the season, the Rally of Portugal tends to serve as a pointer to the relative potential of the main WRC teams on the loose. However, the mud and incessant downpours that marked March's event made any sort of objective analysis of the results impossible. Observers are therefore likely to be paying special attention to the way things unfold this weekend in Argentina. as long as the rain keeps away from this one. But in the foothills of the Andes, winter is fast approaching and good weather is by no means a foregone conclusion. Even so, the battle for number one spot is certain to be yet another fast and furious affair.

Rally Argentina? Ask the drivers and they'll answer practically unanimously that it's one of the best rounds of the entire World Rally Championship. To justify their claim, they'll cite the warm welcome, the enthusiasm of the spectators, the staggeringly beautiful landscapes, the exoticism of the transatlantic trip to South America. and the exceptional variety of stage surfaces it offers. It has to be said, the route around Cordoba does feature an exceptionally broad spectrum of surface types. From Friday's sandy tracks to the slippery lanes of Leg 2 and the rocky mountain passes of the final day, there is effectively something for all tastes. Some parts of the rally are reminiscent of Greece, others of Portugal. And when the heavens open, there are of course the eternal reflex references to Great Britain!

Yet while the drivers revel in the Pampas, the South American round remains a reasonably complex one to call for tyre manufacturers who do not have the possibility of carrying out pre-event testing in the weeks leading up to the rally as they do in Europe. So given the restriction that limits teams to just two types of tread pattern for any one event, it is important to develop and select the compounds and constructions of the tyres with special care in order to cover all the ground conditions possible.

Meanwhile, Michelin will be out to return to the sort of winning ways that saw it harvest an uninterrupted run of seven wins in Argentina between 1992 and 1998. Given their current form, the firm's manufacturer-partners, including 2001's winners Mitsubishi and Peugeot, seem perfectly up to helping them achieve just that.

Tyres and the World Rally Championship
Like any tyre (car, truck,...), a World Rally Championship tyre has to fulfil a certain number of functions: grip, absorb, steer, transmit, resist. To be competitive, it must of course combine all these roles. However, the specificity of each round tends to put the spotlight on one or sometimes two of these functions

Round is one of the events that make the least demands on tyres. Even so, Argentina remains quite a complex rally from the tyre angle, if only because of the variety of stage surfaces and temperatures drivers can face.

Meanwhile, the Andean foothills are in the southern hemisphere of course and the fast approaching winter often spells rain, or even snow.

To optimise traction and grip, the compounds developed for Argentina are chosen with care. On site, the tyres themselves can be finely matched to ground conditions on the day - if necessary - by Michelin's technical staff who hand cut the tread patterns before each group of stages.

Selecting the ideal compound is especially important for the numerous narrow stages that demand frequent re-acceleration in low gears. An excessively soft rubber, for example, can compromise handling since the tread blocks would be too flexible. On the other hand, too hard a choice will tend to favour the phenomenon of microscopic wheelspin.

In addition to careful compound choice, microscopic wheelspin is countered by the design of the tread blocks themselves. As the leading edge of each block strikes the ground, its mission is to 'clean' the track by slicing through the top layer of loose sand, gravel and or mud. This is to ensure the clearest possible road surface for the following rows of blocks in order to transmit the car's power to the ground as efficiently as possible. <pre> M i c h e l i n ' s r a n g e f o r A r g e n t i n a

Clear, hard Michelin Z 17/65x15 The rigidity of the Michelin Z's tread blocks limits their ground mobility on aggressive stage surfaces.

Damp, soft or Michelin ZA 17/65x15 A relatively open tread pattern to penetrate the loose top loose stages surface in search of more compact ground deeper down.

Soft ground or Michelin ZE 17/65x15 or The Michelin ZE differs notably from the Michelin ZA by loose gravel 16/65x15 its more open tread pattern and its availability in two widths.

Very wet ground Michelin WB 14/65x16 A distinctly open tread pattern to ensure efficient and/or rnud clearance of water. Its narrow dimension allows it to slice through the surface layer of rnud in search of a more stable base underneath.

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These products are available in three compounds according to conditions: 7 (cold, slippery stages), 8 (milder conditions) and 9 (warm weather, or hard ground).

Michelin has a total staff of 16 in Argentina. The total number of covers available for the event is approximately 2,340 shipped to South America by boat and plane. All are fitted with Michelin's ATS system (Appui Temporaire Souple).

These figures do not include those teams supplied and serviced by Michelin Argentina.

-Michelin

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