Non N Rated Boxster Tyres - opinions?

[Guest]

My car will require front tyres soon and I've been looking at the different tyres options for 225/40/18. The car currently has Continental Sport Contact2 N rated tyres so I'll probably buy Conti's again to make sure the tyres all match. However whilst searching the net you can buy brand new W rated tyres from Faulken and Kumho (amongst others) for around 130 a pair mail order. Has anyone gone down this route?

 

[gdavison]

Does the use on NON N rated tyres invalidate your insurance ????

 

[Guest]

I don't believe so? I'm insured with Axa and there is no obvious mention of that.

I seem to remember this question coming up years ago when I had my last Boxster and I'm sure some owners said the Kumho's (or Faulken's can't remember which now) were excellent tyres.

Just interested to see if anyone has gone down this route?

 

[critch]

Personally, tyres are the one thing I would not be prepared to compromise on as the handling and safety of the car is almost entirely dependent on that little patch of rubber in contact with the road.

My 987S came fitted with the same tyres as you have i.e. Conti Sport Contact 2 and I think they are quite good tyres giving predictable and manageable oversteer in the wet and are apparently (so far) unstickable on a good dry road. I have no benchmark to compare the Contis with, however, and so I am planning to change over to Michelin Pilot Sports for which I have been quoted £740 for a set of four, fully fitted, balanced etc. That's for 235/40/ZR18's at the front and 265/40/ZR18's at the back.

I'm not sure what the N-rating means technically except that they are approved by Porsche and I was disappointed, for example, to note that you can't get Pirelli P-Zero Rosso's in the above sizes for the Boxster S. Maybe it's down to the load rating which should be 91Y at the front and 101Y at the back? Just guessing.

Critch

 

[Tool Pants]

I have a 1997 with 60k miles. Gone through 2 sets of non-N tires.

Guess I will not be invited to Porsche heaven....

 

[JCB..]

I'm not sure what the N-rating means technically except that they are approved by Porsche

It means they have been tested and not found wanting by Porsche.

I'm sure that any top brand, high-performance tyre, N rated or not, would be quite satisfactory.

 

[jason]

Isn't the N rating given to cars that perform at VERY VERY high speeds by Porsche?


Is it not also likely that Porsche will only test the ones they have a contract with or the manufacturers who come top of the tender list?

Don't know personally just asking the Q's.

J

 

[JCB..]

ORIGINAL: jason

Isn't the N rating given to cars that perform at VERY VERY high speeds by Porsche?


Is it not also likely that Porsche will only test the ones they have a contract with or the manufacturers who come top of the tender list?

Don't know personally just asking the Q's.

J

Porsche 'N' rating applies to tyres not cars.

As not all tyre manufacturers have N rated products your second assumption is probably accurate.

JCB..

 

[Guest]

Moving this on a tad, we are generally talking about road tyres here and the 'N' rating is quite unclear, I feel the insurers will always look for a way out and depending on the payout I feel they will always check the car.

Can PCGB get a definative statement from Porsche on this ?

I have tracked my car recently on the MPS2's and whilst they are good I feel there are a few more better non 'N' rated tyres. Has anyone have any input into trackday tyres ?

 

[THX911]

ORIGINAL: JCB..

ORIGINAL: jason

Isn't the N rating given to cars that perform at VERY VERY high speeds by Porsche?


Is it not also likely that Porsche will only test the ones they have a contract with or the manufacturers who come top of the tender list?

Don't know personally just asking the Q's.

J

Porsche 'N' rating applies to tyres not cars.

As not all tyre manufacturers have N rated products your second assumption is probably accurate.

JCB..

Sorry, I sort of disagree here and I am basing this entirely on a very lengthy conversation I had with a Michelin technician:

It might be worth reading this first: http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=26 (link also available in the Boxster FAQs on the forum)

N rating, I was told, is a very lengthy and expensive process for both Porsche and the tyre manufacturers (thus not every manufacturer takes part).

A 986 (Boxster pre-2004), for example, cannot take Michelin Pilot Sports 2 (PS2) as they have not been N rated but you can get N rated PS2 for the 996 as it is down to supply and demand. Michelin took the decision that they will be demand for PS2 by 996 owners and went for N rating them but didn't feel it is worth for the 986 (as he kept insisting it is not a trivial process and it is costly), so we still have to use the Pilot Sports original, they can rate them in the future (BTW, 987 and 997 tyres are different size from 986 and 996 for the same rim size). That is why it sort of depends on the cars but then the Mich guys also told me that the new PS2 non-N rated tyres are very similar to the N rated, so I can use the non-N rated PS2 on my car but at my own risk as he said he is fully aware of the warranty/extended warranty issues, possible insurance issues, etc...

If you get a chance, see a non-N rated Pilot Sport and an N-rated Pilot Sport; the thread patterns are very different; though having said that with the PS2 they are very similar, so I assume these manufacturers are probably using the extensive testing with Porsche and then making all their new high performance tyres similar to minimise cost or probably all modern high performance cars are getting similar in terms of tyre requirements(?).

 

[Black80XSA]

Very well put THX911 and to take it on a step further, i'm not sure that the Conti SportContact2 was approved for the 986 either - my recollection of 2004 models was that they still came on the original version of the SportContact.

I think the insurers would be hard pushed to refuse a claim on a car shod with quality rubber, even if N rated. I mean, there are plenty of other performance cars sitting quite happily on Goodyear F1s, Toyos and such like.

 

[oceancarrera]

ORIGINAL: Oxtailsoup

My car will require front tyres soon and I've been looking at the different tyres options for 225/40/18. The car currently has Continental Sport Contact2 N rated tyres so I'll probably buy Conti's again to make sure the tyres all match. However whilst searching the net you can buy brand new W rated tyres from Faulken and Kumho (amongst others) for around 130 a pair mail order. Has anyone gone down this route?

W-rated tyres indicate the max speed rating that the tyre can operate safely under normal road conditions (W = upto 186mph). This is not quite the same as the "N" rating given for Porsche-specific tyres. Your Boxster will not be able to achieve 186mph in standard form [] so I would agree with John that the tyre is probably perfectly safe for normal road use. Other than the marketing bumpf, I have never seen any quantitative evidence that empirically shows N-rated tyres to be able to perform at a higher level than the equivalent non-N-rated tyres. FWIW, most trackday tyres are not-N-rated yet these are able to perform at a much higher level than any N-rated tyre available.

With regards to using a non-N-rated tyre and the impact is on your insurance, however, is another issue that has never been properly answered by any underwriter AFAIK.

Getting dedicated type approval for any single manufacturer is a hugely time-consuming (cost-consuming) process for the tyre manufacturers. I suspect that much of this was borne out of the car manufacturers not wanting to engage in any legal matters should a "normal" tyre blowout or be found to be the cause of an accident. (think Ford vs Firestone...). Car manufacturers could partially protect themselves by insisting that a type-approved tyre were used, and if not, the car manufacturer would not be found liable in the instance of a tyre-fault-accident should a non-type-approved tyre have been used. At the same time, the car manufacturer is able to work with the tyre companies on designing a compound/pattern/construction-optimised tyre for their cars.

 

[penfold944]

Its coming back to me....

I remember that we went on a visit to the Bridgestone facility in Ireland a few months back and they explained the difference with N rated tyres to us.

As far as I recall, it has to do with the contruction of the sidewall. As Porsches are traditionally rear engined, or mid engined ( they keep moving that 996/997 engine forward a few mm ) - normal tyres arent designed to take that extra weight on the rears. As a result, the sidewalls are beefed up to be stiffer. I mean its not like you are going to deviate on what tyres to put on a lambo or a ferrari. I guess Porsches are just a little bit less exotic.

I remember someone else gave me an example of a fairly new 964 that came into the OPC in Belfast a few years ago. It just didnt feel right on the road at speed. It turned out that the rears had been replaced with non-N rated tyres and that as the tyres warmed up, there was movement in the sidewalls.

It could just be all a bit of marketing junk - but to be honest, I'll stick with N rated personally. Its not really a big deal to get the tyres approved and specced for the car.

 

[JCB..]

ORIGINAL: penfold944

Its coming back to me....

I remember that we went on a visit to the Bridgestone facility in Ireland a few months back and they explained the difference with N rated tyres to us.

As far as I recall, it has to do with the contruction of the sidewall. As Porsches are traditionally rear engined, or mid engined ( they keep moving that 996/997 engine forward a few mm ) - normal tyres arent designed to take that extra weight on the rears. As a result, the sidewalls are beefed up to be stiffer. I mean its not like you are going to deviate on what tyres to put on a lambo or a ferrari. I guess Porsches are just a little bit less exotic.

I remember someone else gave me an example of a fairly new 964 that came into the OPC in Belfast a few years ago. It just didnt feel right on the road at speed. It turned out that the rears had been replaced with non-N rated tyres and that as the tyres warmed up, there was movement in the sidewalls.

It could just be all a bit of marketing junk - but to be honest, I'll stick with N rated personally. Its not really a big deal to get the tyres approved and specced for the car.

So based on that Porsche models 924, 944, 968, 928 and Cayenne don't need N rated tyres then?

I also hadn't realised that a tyre was manufactured specifically for fitment on a rear axle.

 

[nemc]

ORIGINAL: critch

Personally, tyres are the one thing I would not be prepared to compromise on as the handling and safety of the car is almost entirely dependent on that little patch of rubber in contact with the road.




I agree with Critch!

 

[penfold944]

Well what we were told that the tyres had a significantly different construction. The explanation we got was that the rears had to cope will a lot of power and the weight of the engine - not really an issue with a front wheel drive car.

As for the 924/944/968 etc - I think N rating came in in the early 90's which obviously predates those cars. I'm sure the Cayenne uses N rated tyres.

 

[Guest]

I think John is refering to the fact that those cars are not mid/rear engined. Not the year.

I started this thread because someone mentioned a few years ago an another board (I think it was the 986forum) that Kumho's were actually better in their opinion for all round grip and many other owners seemed to agree (and plenty didn't). I was just wondering if any other owners had gone down this route or is everyone on N rated?

 

[penfold944]

ORIGINAL: Oxtailsoup

I think John is refering to the fact that those cars are not mid/rear engined. Not the year.

I started this thread because someone mentioned a few years ago an another board (I think it was the 986forum) that Kumho's were actually better in their opinion for all round grip and many other owners seemed to agree (and plenty didn't). I was just wondering if any other owners had gone down this route or is everyone on N rated?

Lol [] I did get that - but I dont have an awnser for that one... so a bit of glossing over on my part I'm afraid.

I dont honestly know... but anecdotal evidence I have heard from a few people is that there is a difference in the handling of the cars on non N rated tyres...

 

[JCB..]

ORIGINAL: Oxtailsoup

I think John is refering to the fact that those cars are not mid/rear engined. Not the year.

I started this thread because someone mentioned a few years ago an another board (I think it was the 986forum) that Kumho's were actually better in their opinion for all round grip and many other owners seemed to agree (and plenty didn't). I was just wondering if any other owners had gone down this route or is everyone on N rated?

Jason

The only reason my tyres are N rated (Conti's) is because I got a good deal over the last 5 years from my boyhood chum who ran 3 Protyre outfits. He has now flogged his business so I will be looking around for similar deals.

I certainly wouldn't turn down a tyre at the prices listed earlier but how easy would it be to get a fitter to put on tyres that they didn't supply and at what cost?

JCB..

 

[Guest]

I certainly wouldn't turn down a tyre at the prices listed earlier but how easy would it be to get a fitter to put on tyres that they didn't supply and at what cost?

JCB..

From my experience -£84, that was for a mobile service- I supplied the tyres, he fitted the tyres, balanced 'em and fitted 'em.

These were for my trackday wheel/tyre combo

I had no other way of getting the wheels/tyres to a tyre fitting place [8|]