VGM911

The case for using N-spec tires is made quite persuasively and convincingly by Porsche.

For those of you who have decided against N-spec tires, can you share with us why you purchased the tires you bought, what your ownership/driving experience has been with those tires, and whether you plan to buy N-spec tires the next time. Thanks.

Mr. C4

I was asked to test (sponsored a the time) a set of Toyo T1R and they stayed on for 2 weeks.........................

Jake Ok

Why only 2 weeks. Toyo makes a great tire. Please share

jjker

I don't know what N spec is, but I run Eagle F1 GSD 3's and love them. I don't track the car.

What is N Spec? I find it rather hard to take if it's a porsche approved list of tires that are suitable for the car, I mean, it's not like anyone would be running old bias plys or something off an old ford truck on there...

gota911

jjker - here is a good explination of the Porsche N rating for tires.

http://www.tirerack.com/tires/tirete....jsp?techid=26

newport996

Yes, Porsche says us should use N-Spec tires....I got a NEW set of non N spec tires in my size for $200...they were just sitting in a shed and my bodyshop wanted to get rid of them...just happened to be the same sizes I needed..so I bought them....I have no issues...mine are Conti Sports, just not the N-Spec...they make them in bot N spec and not...I have no issues. One thing is that the tire company must pay for Porsche to certify and I also think they have to make a variety of Porsche sizes...so some companies (Kumho, Toyo, Yokahama etc) have not had their tires Porsche "certified"...I think if you get a good tire company you will be fine.

CosmosC4S

Do people who stick religiously to Porsche's recommended 0-40 oil,
also strictly use only N-Spec tires on their cars?
Just as with oil, I'm sure Porsche's experts have spent lots of $$ and time on research for the best performance and safety tires for their cars.
Afterall, tires are just as important, if not more so,
The whole car, and it's occupants depend on them.

newport996

Not the same as oil....if you dont pay Porsche to test your tires and make them in a variety of Porsche specific sizes, they wont give you a certification....So for example...Kumho does not make a GT3 size tire, or a 19" 997 size tire, etc....even if one of their 17" tires passes the specs for the 986 and 996...they could not get a certification. So in some cases it has NOTHING to do with the tire. Also I wonder what the actual difference in teh Conti's I have and the N spec Conti's....its a $10 difference...I wonder if that $10 is just to makeup the cost to get it certified....and they only pass it along to the Porsche owners....like I said in a previous post....if you get a good tire...then you will have nothing to worry about....

ElTorrente

I think it's like "THX certified".

Just because your amp/reciever isn't THX certified doesn't mean it isn't up to specs. It just means that the maker didn't pay the money for testing/certification, even though they surpass the specifications and will perform just as well.

1999Porsche911

Tires, coolant, and oil as well as many other componants such as plugs. filter and the like, are all paid certification for car manufacturers. If you do not pay, you do not get certified. This practice is legal and has existed for more than 70 years. Certification does not, in any way, mean the componant is the best available.

RAC

One question with N spec tires. Do you have to have all matching N rating for all four tires? For example, say you have N1 on the fronts and say you had to replace the rears but could only get N2 on the same brand of tire as the front. Is this ok or do they need to be all the same N rating?

MarkinMD

Let me start by saying that I am far from an expert on this. When I was shopping for new tires for my Boxster a few years ago, I compared Bridgestone S02A's. The N-rated version had a very different tread design than the other S02's. I also heard from a reliable source that the N-rated Bridgestones had a different construction with stiffer sidewalls. (Sorry I don't remember the source.)

As I recall, not all n-rated tires have the same number of plies or construction (nylon, rayon, steel, etc.) as the non-N-rated versions. It is my understanding that the tire manufacturers are not just paying for a "certification" but are building a tire that will meet Porsche's performance criteria. I guess that is what the Tire Rack site says, too...
http://www.tirerack.com/tires-techpage-1/26.shtml

I just did a quick look at the spec sheets on the Bridgestone, Pirelli, Continental and Yokohama web sites. None of the spec sheets covering tire models that carry an N-rating showed the actual tire construction so I could do a comparison between N-rated and non-N-rated. Hmmm...

Luckyr

No, the number after the "N" has to do with the version of that tire size. Any N is fine.

Luckyr

I haven't done it yet but I will be getting non N rated tires next time. Why? because Michelin PS2s are not available in my size (03 C4S) for the front tires.

Ray S

I think it is really a disservice for anyone to imply Porsche's N-spec program is little more than a certification program that tire manufacturers simply pay money to get their tires on the list. At least one magazines I have seen did a detailed article about the testing and certification process and they described it as an extremely involved and intense process. If memory serves, the article went so far as to say that Porsche puts more effort into matching tires to their cars (and truck) than any other manufacturer on the planet. Finally, it is my understanding that Porsche N spec tires often differ in many ways (tread pattern, construction, compound, etc.) from the same model tire that is not N-spec. Porsche has built much of it's reputation on the outstanding handling characteristics of its cars. It makes little sense for them to risk that reputation by putting on substandard tires that they made some certification money on.

That being said I think there are many reasons one could have for choosing a non-N spec tire. One example could be track use as the only R-compound or track tire Porsche currently test (that I am aware of) is the MPSC for the GT3. A second reason might be cost as there are many lower cost alternatives available in the correct sizes.

In my opinion, this situation differs greatly from the "oil" debate for one simple reason. It is very easy for even a novice enthusiast to swap out the tires, drive the car around (or better still take it to the track and compare lap times) and make a seat of the pants judgement about the handling and ride tradeoffs. With oil, the only way you can really know which oil is absolutely better would be to perform life tests on multiple motors (under different environmental conditions) and then tear the engines down to check how each oil worked. Additionally, if you decide to experiment in your own car with oil you may not see the ultimate wear problems (or benefits if your are right) until years down the road.

The bottom line (in my opinion once again) is;
It's easy to throw on a new muffler and judge the sound, or put on some headers and check the results on a dyno, or put a bigger shim in a GT3 spoiler and judge the handling/straighline speed trade-off, or measure lap times on a set of tires. I just don't see how you accomplish the same kind of tests with oil without a huge amount of raw speculation or big money.