Winter tyres - UK

[GTF]

I have searched the forums and have read through the various views and recommendations but I still have a further question that I hope someone will be able to help me with.

For the UK, I have been told that tyres must have an "N" rating, which indicates that the side walls of the tyres are of sufficient strength to prevent them from popping off the rims due to the high forces involved in corning. I am looking to fit winter tyres but non of the suppliers are able to provide this N rating, but have stated their tyres will fit the car (MY '99 996 C4). Tyres that "fit" are one thing but tyres that stay put during cornering are another. I have have found 3 suppliers - Michelin (way to expensive), Bridgestone Blizzaks and Vredestein Winter Xtreme, and was wondering if anyone has any comments / recommendations / experience of fitting wnter tyres in the UK and this N rating issue.

Thanks.

[londoner06]

Hi GTF, I found a link to the current Porsche winter tire recommendations from the USA site. Maybe it will help?

Overview winter tyres current vehicles

Alex

[berty987]

The N rating has nothing to do with tyres popping off the rims , the N rating is to do with the tread block and rubber compound. These are optimised to give the best grip and comfort for a Porsche application , by getting the tyre to temperature as quickly as possible and coping with the lateral forces of a high performance rear/ mid engined car. Often the load index on an N rated tyre is actually less than that of the non N rated version. Winter tyres are a lower speed rating than summer versions so the performance is already somewhat impaired as a result. The N rated version is usually only a few pounds more than the standard, so when purchasing a full set of tyres specific for winter , its a marginal increase in cost for total peace of mind. Michelin tend to be expensive because they are generally accepted as being the best. Before you discount the michelin option I would suggest reading the technical information on their tyres. If your only interest is keeping mobile during winter months and you can accept a change in driving style , non N rated vredstein tyres are probably quite acceptable. If you plan on driving your Porsche with an element of enthusiasm , then I would suggest an N rated michelin or Pirelli will ensure you stay on the road and are not subjected to any nasty surprises. I test drove my 987S in Germany with michelin alpin tyres in January at -15C and 1.5 " of snow. Only when provoked did the PSM need to take action , the car felt comfortable and secure on both snow and gritted tarmac. In europe the average temperatures in winter are below 7C (lowest temp which summer tyres operate properly) for longer than here in the UK , therefore winter tyres are mandatory in some countries. Winter tyres should be changed back to summer versions when the average temp gets above 10C as they will wear at a quicker rate and are not optimised for higher temperatures and speeds.

I assume you are looking for 205 55 16 and 225 50 16 sizes ?

I think you wil need to get a 215 55 16 for the rear , the rolling radius will be similar and can be checked on the web site below.

You may find the following links of interest :

http://www.carbibles.com/tyre_bible.html - info on winter tyres and the N rating

http://www.michelin.co.uk/michelinuk/en/ca...0314172027.html -Michelin alpin Tyres

Edited December 4, 2008 by berty987