bal

With all the recent IMS threads, I figured I might as well start another topic that could devolve into a boobies thread: N versus non-N rated tires.

I have done some searches (honestly) both here and on Google and haven't really seen anything that objectively describes the benefit of N-rated tires. What I've seen can be summarized as some version of: "N-rated tires are Porsche approved and you must use them", "they have a different formulation to non N-spec tires", "you have a Porsche, why are you scrimping on tires?" and "your warranty and/or insurance will be void if you don't use N-rated tires."

Courtesy of the previous owner, my car has Sumitomos: 225/40-18 at the front and 285/30-18 at the back. They're OK in the dry and not great in the wet, which is an important consideration where I live. I may occasionally do some high-performance driving on a track, but by and large I'm on normal roads driving around and am unlikely to exceed 90mph. So with that in mind, what should I get?

According to our friends at Tire Rack (who apparently supply Porsche NA dealers), I could spend anywhere from $500 for four Sumitomo HTR Z III (not N-rated) to $1200 for four Bridgestone Potenza S-02 A (N3-rated). The cheapest N-rated tires are the Pirelli P Zero Rosso at about $1000 for four. That's a big difference compared to the Sumitomos!

Looking at the published specs on Tire Rack, I see that the Sumitomos have a 92Y service description (1389lbs, 186mph) and a UTQG of 300 AA A (3x standard tread life, >0.54g traction and able to run >115mph). The N-rated Pirellis do not indicate a service description other than being Z rated and a UTQG of 220 AA A (2.2x standard tread life, >0.54g traction and able to run >115mph). The non N-rated versions seem to have a service description of 92Y or 93Y, so comparable to the Sumitomos. From these specs then, there appears to be little difference between them.

I've heard good things about the Continental ExtremeContact DW 92/93Y 340 AA A and they come in at $774 for four, and the Hankook Ventus R-S3 seem to be the new hotness but are apparently unavailable in the required size for the rear wheel(?). For the 225/40/-18, they have a service rating of 88W (1235lbs, 168mph) and a UTQG of 200 A A (2x standard tread life, >0.47g traction and able to run >115mph). Purely from these specs, they are "not as good" as either the Sumitomos or the Pirellis but realistically I am unlikely to exceed their limits!

c4racer

The hankooks and sumis are decent for the $ but won't last as long or stay as sticky or quiet over the life as a higher quality tire. That is a lot of what you pay for. My favorite perf tire right now is the pilot SS which I have on my M5. Fantastic tire and consistent over the life which is pretty long for a summer perf tire. Also great in the wet. Not sure if those come in your size but worth a look.

The Pirelli Pzero are good too. I've had those on a few cars and currently have the porsche spec version on 997 rims on my car. No complaints wet or dry on those either.

tshort

Doesn't really address OP's question, but I just did a related tire investigation and ended up going with Dunlop Direzzas based on this thread: https://rennlist.com/forums/996-foru...0-and-x51.html

Gulliver

I bought N rated tires because I researched it enough to become convinced it was important. N-rated tires have been tested and approved by Porsche for my 911, that's good enough for me.

dgjks6

I've looked too. No one says what goes into a Porsche approval. And the reality is that is does not matter. If it did, with all the Porsche's with non N tires, we would know.

But with tires, you generally get what you pay for.

If you look at the tests on tire rack - about the only place that actually compares tires, you will see faster lap times for the more expensive summer tires than the cheaper ones (again, generally).

5CHN3LL

Porsche approves certain tires for its vehicles, often because the tire manufacturer worked with Porsche to ensure the tires were suitable for the vehicle's weight and performance requirements. If you want to ensure that your service manager at the Porsche dealership continues to like you, or you prefer to not spend a lot of time researching tires, buy an N-rated tire.

Regardless of the N rating, any tire that meets the load, speed, and size requirements for your vehicle can be used.

For example, the Hankook Ventus V12 evo2 tires I am currently running are acceptable for the weight (load) of my 996, rated for speeds up to 186MPH, and are perfect for the conditions in which I drive (warm, dry asphalt).

If you choose to explore the many non-N-rated tires that are out there that will fit your 996, make sure you understand the speed ratings for tires and the performance and load characteristics of your vehicle.

You will hear that running non-N tires will void your warranty. I did not find this to be true with my 986 - the dealer didn't even attempt to use this bogus reasoning. Less scrupulous dealerships will often use this ploy to try to dodge warranty repairs. Learn about the Magnuson-Moss Warranty Act, which exists in part to prevent manufacturers/dealers from denying warranty claims for bogus reasons.

You will hear that running non-N-rated tires will jeopardize your life. If you run a tire that meets all of the requirements for your vehicle, I do not believe you are more likely to die than if you're running an N-rated tire - assuming you're not driving maniacally. If you're running a non-N tire rated for 200mph AT 200mph and you drive into a cow, you are probably going to die, and it's probably not the tire's fault. If you are driving on a tire rated for 100MPH and the tire disintegrates after 15 minutes at 150MPH, this is your fault, not the tire's fault.

You will hear that you are a sorry excuse for a Porsche owner if you "cheap out" and buy non-N-rated tires. If you give a quarter of a damn about what other people think about your purchasing decisions, you're a sheep and you deserve to live with the smaller selection and often higher prices associated with N-rated tires.

You will hear that "you get what you pay for." Many factors go into the pricing of a tire, including the brand, the size, the popularity of the tire, the age of the design (sometimes newly released models are priced low to drive interest and initial adoption, and the prices increase once the hook is set). Sometimes tires become difficult to find and this scarcity drives the price up. And yes, sometimes the tire manufacturers gleefully rub their hands together as they gaze out over warehouses full of N-rated tires, knowing that MOST people are just going to buy the N-rated tire without a second thought.

While it's not reasonable to assume that an ultra-high-performance "luxury car" tire is going to cost the same as a snow tire for a Ford Ranger, it's also unreasonable to assume that cost is the only metric by which you should evaluate which tire to buy.

If you go online, read a bunch of glowing reviews for a specific tire from people with cars similar to yours, with similar applications to yours, and find that it meets all of your vehicle's requirements, you may have a compelling reason to try that tire. If, however, you're standing there looking at two heaps of tires, and you choose the one that's more expensive solely because it costs more, you deserve to pay more AND to be called names.

Byprodriver

UTQG mileage rating (100,300etc) testing is performed by the manufacturer of the tire. (unless this has changed since the UTQG ratings started about 30 yrs ago) So it is decieving to compare mileage numbers between competing brands. Basic guideline comparing different models of same brand. Speed ratings you pointed out are almost irrelevant unless you plan to cruise at 130+ MPH for longer than 45 minutes on a hot day. Although the speed ratings do infer performance characteristics. I believe you would be most happy with Michelin Sport AS3 or Super Sports depending "weather" you drive in the rain often.

JayG

Hankook and Sumitomo are not less than high quality tires, in fact Hankook has some of the higherst rated tires. They will stay "stickey" and perform better as long or longer than some more $$ tires. In tires higher $$ does not necessarily mean higher quality


+1

I have Hankook V12's on my Boxster and love them. They are a great value and at or near the top in all performance categories for summer tires. The new version Evo2 is a 320 tread wear. I had Potenza SE-02 (N3) before and they perfiormed well, but tread life was crappy. The Hankooks are less than 2/3 the cost of teh SE-02's

My 996 Targa has Michelin Pilot Sport A/S3's and frankly I don't like them. Great tread wear(500), all season and pretty good performance, but extremely noisy. When they need to be replaced I will probably put on the Hankook V12's. IMHO, Michelin tires are a bit overrated

A lot depends on how you plan on using your car. If it is just street, you will want different tires than if you do a lot of AX and different again if you track your car

As far as the N rated vs regular, I too could not find a definitive answer to the difference other than Porsche has approved specific tires for specific cars. What may be approved on a 996, may not be on a 986 or a 997 or 991, etc . Even an 18 may be approved but not a 17 or 19

Supposedly, there "may" be a difference in tread compounds or some secrete sauce. IMHO, I'm not concerned with N rating. I also understand that a Porsche dealer will not sell anything that is not approved for your car

911 carrera blue

The original tires of my car were the Michelin, I bought Sumitomo, is not my daily driver and I just cruise no autocross or track they have been working fine for me.

Sent from my iPhone using Rennlist

Cuda911

Excellent reply by Schnelly. Wish there was some way to ensure that this info. comes up at the top of a tire search query.

johnireland

I bought my car with N3 Continentals on the back (ZR rated) and none N versions of the exact same tire on the front (Z rated). My Porsche dealer would not balance my wheels with the non-N rated tires on the car. He told me that the 911 configuration of weight and driving characteristics has Porsche requiring specific qualities in their tires. The tread pattern may look exactly the same but compounds and belt design can be different between N rated and non-N tires.

He did not tell me to change front tires...they were brand new and would be fine for normal street driving. However I am very fussy...so I found some N3 rated front tires and put them on. If I am driving aggressively...no track speeds but aggressively...I feel that there is a difference in the turn in between the two versions of the tires. That is my non-scientific personal experience.

Porsche as a manufacturer has both its performance reputation and as well and legal responsibility to put together a package that delivers the maximum out of the car...and does so as safely as possible. We have all been drawn to these cars because of how the designers made them...for decades. I'm willing to go with their choice of tires.

Macster

For myself, I am not prepared to 2nd guess Porsche nor use my car as a test bed and use my money to try to expand the set of tires that are known to work on Porsches.

When I test drove my Boxster before buying it I was quite happy with the way the car rode, steered, braked and just felt. I had no reason to when it came time to replace the tires to try non N-rated tires.

So far with N-rated tires, every set of new rear tires or every set of new front and rear tires feels the same, even though sometimes I use different brands with different (sometimes higher, sometimes lower) N numbers. I have never mixed brands, nor even N-numbers.

The same applies to my Turbo.

Now of course a number of owners have strayed far afield regarding tires. And for the most part have not experienced major upset. At least they have not reported any.

However, I note a few owners have admitted to the car not feeling right with non N-rated tires and going so far as to switch back to N-rated tires.

This raises the question of are the owners who report "no problems" running non N-rated tires just not that tuned in to their car's handling, road feel, etc? Or are the owners who report problems just being nitpickers or have over active imaginations?

Who knows?

All I know is as I mentioned above so far with Pirelli or Michelin N-rated tires on my Boxster and either Continental or Bridgestone N-rated tires on my Turbo I have not had one moment where I wished for a different tire. (Well, except a few times when driving in snow with summer tires or when driving in rain on tires that I should have replaced beforehand.)

While the N-rated tires are I'm sure more expensive than non N-rated tires the car always feels the same and behaves the same with the tires new or just before they are replaced and everywhere in between. This consistency in pefrormance, tire life, and what have you is worth something to me.

So, it is up to you. Stick with N-rated, in fact just follow Porsche's rules/guidelines on this matter and essentially put tires out of your mind, or ignore Porsche's rules and guidelines and use what you want, what fits, hopefully tires with the same metrics as the N-rated tires, and possibly you can still put tires out of your mind. But you have to be prepared that if the non N-rated tires don't suit you or the car to possibly have to prematurely replace them.

bal

Thanks for the sensible discussion. Schnelly put into words what I've been thinking. It seems that outside of Porsche engineers and the tire manufacturers, all we know is that we should go for N-rated tires because "Porsche knows best". Ultimately is down to us as individuals to make a choice, but I feel that using "Porsche knows best" reasoning would also imply that we would never replace oil sooner than Porsche's recommended service interval or replace the "lifetime" coolant. I will resist bringing up our favorite bearing...

bal

If anyone is interested, here is the latest approved list (996 is on page 2) http://files2.porsche.com/filestore....5-001a64c55f5c I did not realize that the 18" rear wheel tires changed between the 996.1 and 996.2. According to this document, the rear tires for the 996.1 are 265/35ZR18, whereas for the 996.2 the changed to 285/30ZR18. The wheel size seems to be the same 10Jx18 ET65 though.

Dennis C

I tend to agree with Macster on this issue.

The Porsche N rating is given to tires that have been tested by Porsche and that provide the performance characteristics that Porsche desires for the car. There may be other tires that deliver similar performance that haven't been tested and therefore aren't N rated. As a Porsche owner, you have to decide if you want to pay a premium for N rated tires and accept the Porsche performance standards, or if you want to choose another tire based on your own expectations for your car. For example, you may decide that you want to spend less money on tires. You may decide that you want a tire that offers longer tread wear life. These tires probably won't meet Porsche's standards, but they will meet yours.

Porsche tries very hard to protect the brand image, and a big part of that is producing a car that delivers consistent performance. Tires can impact performance so much that Porsche decided to recommend a group of tires that deliver consistent performance. If you buy something that they don't recommend, then they can't guarantee the performance.

So, that was my long-winded way of saying that buying tires that aren't N rated isn't necessarily a bad thing, it's just taking your chances with the way the car will handle. Some people will say that they can't tell the difference. Some people will say that they get better performance with a specific tire. If you don't want to try to find the right tire by trial and error, then buy N rated tires. If you are really comfortable with another tire, then buy that one.

I've tried many tires on my Porsches (some N rated, some not) and I've never found a tire that I like better than the N rated Michelin Pilot Sport PS2. I will continue to buy them for now.