Okay, I have been hearing lots of different stuff about the N ratings and the PS2s in the stock 225/40 and 295/30 sizes.

I am not saying any of this gospel and it may all be inaccurate, but it is what I have been told by three people at tire rack and my dealer service representative.

The N rating simply means that Porsche has YET to use the tire as OE. I have had the word yet stressed to me as the PS2s are very new and Porsche may end up using this very tire, but that would require a crystal ball.

The sizes 225/40 and 295/30 are actually extra load designation which would have a stronger sidewall and should lead to better handling. The different construction issues for N tires may be not be accurate, but I did not go into each different tire make and if concerned you should inquire. I just inquired about N rating in general and the PS2s.

Take it for what its worth, and again, those people I have talked to could be mistaking. I, however, am getting a consistent opinion from everyone I have spoken with about this tire.

 

Once again, If you are adamant on only getting the PS2's I would just call Michelin directly and get the accurate information. Call 1-800-847-3435 and ask for someone who knows the truth.

 

First you say call tire rack. They say something different than you and now you say call Michelin. Again, I am not interested in being right, just want to know if I should keep the tires as I still have time to return the tires if necessary. Has someone from Michelin told you something contrary to what I have heard. I have been on hold with Michelin for about 5 minutes now . . .

 

Check this link to Tire Rack which explains the "N"designation. http://www.tirerack.com/tires/tirete...al/porsche.jsp

 

Okay, Michellin has spoke. No difference in sidewall construction between the N rated PS2s and non-rated. They think I will be extremely happy with my choice. Nothing like a wild goose chase . . .

Bruce, thanks for the link, but I posted that yesterday or day before when I first raised this issue. Tire rack has been consistent about Porsche prefers use of N and dealers may not install non-N, but that (at least with the PS2s) there is no difference in construction and it may just be that Porsche has YET to use them as OE. They are actually closer in size and have better load capacticies than other N rated tires.

 

The N rating means Porsche has approved the tire for use on its cars. My '04 Carrera has Pilot Sports that are N1 rated, so the part about "Porsche has YET to use the tire as OE" isn't correct. I've had N rates tires come with all 3 996s I've bought.

 

I'm surprised tirerack is saying "N" rating doesn't matter. That's why I suggested talking to Michelin. Here is an excerpt from the link Bruce posted. It pertains more to internal construction and tread compound vs sidewall construction.


"It is recommended that only matching tires be used on Porsche vehicles. Since many Porsche vehicles are fitted with differently sized tires on their front and rear axles, this means matching the tire make, tire type and N-specification. If a vehicle was originally delivered with N-specification tires that have been discontinued and are no longer available, it is recommended to change all four tires to a higher numeric N-specification design appropriate for that vehicle. Mixed tire types are not permissible.

It is also important to know that while Porsche N-specification tires have been fine tuned to meet the specific performance needs of Porsche vehicles, the tire manufacturers may also build other tires featuring the same name, size and speed rating as the N-specification tires for non-Porsche applications. These tires may not be branded with the Porsche N-specification because they do not share the same internal construction and/or tread compound ingredients as the N-specification tires. Using tires that are not N-specific is not recommended and mixing them with other N-specification tires is not permissable."

 

I think Doug H is referring to the PS2's Pilots, not the Pilot Ribs!

 

I am really not trying to argue or win any argument as I can easily send the tires back since they are sitting at my dealer, but you guys are not reading what I am saying and have caused some confusion that lead me to make quit a few calls and etc. It may also be my fault for not being real clear though.

I am only talking about PS2s here. The tire is new and Porsche may well end up using these instead of PSs. That is the yet. As far as PS2s are concerned (I have not confirmeed any other non-N rated tire), they are closer in size than the N rated tires, support more weight, have a better sidewall construction, are built no differently than N rated PS2s and everyone has said they will be better performance wise on the TT.

 

No arguments here! I'm just as interested in learning the truth too. I'm only going by what I read. I personally haven't talked to tirerack or Michelin about PS2's. I have Pilot Ribs. If Michelin swears that their non "N"-rated 225/40/18 PS2 is manufactured no differently from an "N"- rated 235/40/18 PS2, then keep what you have. If that's the case, why bother to listen to Porsche telling us to make sure to keep all 4 tires "N" rated.

 

I would actually bought the rib, but for I did not think about them or see them pop up when I clicked on the Michelin brand logo at Tire Rack. Also, very few tires come up under the search for 996 TTs at Tire rack. I ended up defaulting to a brand search as opposed to vehicle search and actually ordered the PS2s while on cell phone from my car on recommendation of tire rack representative.

 

I'd bet that most "N" tires have the same construction as non "N" tires. There may be some isolated cases where construction is different. About a year ago a Pirelli tech said that one of their N tires had an extra tread belt. This was to prevent the tire from growing in the center at ultra high speed. Even if the tires had slightly different sidewall construction you could compensate by fine tuning the tire pressure.

 

Doug H,
Thanks for doing the research and posting the info. I am going to order the 18in PS2 225/40 and 295/30 also.