S Type 2.7D Tyre Choice / confusion

[John D9395]

Hi. my S Type is due for tyres shortly, and looking on 'tyresaings.com' who I always use, I am confused as to what is on the car, and what is on the web site.

The car curently has Continental 245/45ZR17 Sport Contact-2.

The nearest I can find with a 'z' in it is a 245/45R17 Z Sport Contact-2 J

Is the 'J' for Jag?

Looking at other makes on the site, none have a 'z' in the reference.

On my wifes car, I am looking at moving from Continental tyres to Avon, as they are cheaper, still a good tyre, and have better all round spec with the new efficiency / wet weather / noise ratings.

I was therefore thinking of Avon for the Jag, but as above, I am confused at what the Z means within the Continental description, I don't want to put the wrong rating of tyre on.

Hoping someone can help?

[NormanD]

John D9395 said:

The nearest I can find with a 'z' in it is a 245/45R17 Z Sport Contact-2 J

Is the 'J' for Jag?

Z is the speed rateing

Yes J is for Jaguar, although providing tyres without the J have the same weight rate they will be fine

[John D9395]

I thought about the speed rating, but on the basis that the wife's car uses 'w' rating and is quicker than mine,and 'Y' max is 186mph I assumed is was for something different other than speed.

Just found a site that states Z as being +149mph, I assume I can use V, W or Y speed ratings as long as the load rating is correct?

Why have 2 letters that cover the same speed rating?

Looking for a good branded tyre, but want to make sure its right.

Thanks

[PlayersNo6]

This thread might help OP :

http://www.pistonheads.com/gassing/topic.asp?t=785...

Check the handbook to see if you need Y or W as a minimum.

[John D9395]

The link is interesting, resolved a lot of the confusion I had as to the history of the overlap between ZR and W - Y.

Handbook says ZR for the 245/45 tyres fitted to my car, but 'Y' for the 235/50

I therefore assume that 'Y' would be OK?

I guess it only needs to be correct so that if you have an accedent the insurance company can't wriggle out due to 'wrong tyres being fitted given we can't drive over 70mph?

[littleredrooster]

They'll be fine. I've had Falken 452s on mine for the past 30000 miles and they were great, but are no longer made. Currently wearing some Firestones which seem equally impressive. 245/45ZR 18 is the size/rating