After reading Clarksons review and after having a flat in our Panamera on the sidewall of the drivers rear tire (with less than 2000k on the car! and the tire was toast so it had to be replaced), and waiting 3 days for it to get fixed at the dealer because the tire needed to be "N" rated, I am wondering if the tires supplied on these cars are too soft and puncture friendly. Has anyone considered changing them to something else, and if so what kind? Why does Porsche require "N" rated tires anyways? Wouldn't a properly speed rated tire from any manufacturer do the trick?
I'm curious because I don't want to get a flat and have to tow my car because the local shop cant get the tire Porsche says to get.

 

I suspect it is as simple as $s.

 

From what the saleguy told me, The "N" thing is Porsche specific. The tires are made with that rating for Porsche. But what is the difference between a normal and "N". $$$ is one reason, perhaps, but we purchased the tire warranty, so it was all covered, including the tow, which is great. Maybe I should have simply banked the money for the warranty and used it to purchase a different set of tires.
Im asking because when I get my 991 baby, I want to either buy the tire warranty or get different tires and I want opinions on whats best to do.

 

There's been a lot of debate about this N rating on some of the UK forums. It sounds like it is just Porsche trying to make more money (but I'd love to hear another explanation).

 

That's what I have been told by my local tire shop too (and they sell Porsche and other brands-certified tires as well as the 'generic' versions). There may be some specific features to the N-rated (i.e. bigger 'lips' on sidewalls of certain type of tires... But not really sure) and/or quality check, but the generic will do the job with no problem. I can not imagine that a major tire manufacturer would sell an inferior (meaning less reliable) generic product for the same speed/load rating.

 

Sports cars are often described as vehicles that "stick to the road." Sports car tires make a major contribution to this phenomenon. These tires are very complex products meeting numerous, largely contradictory demands. Finding the proper structure that balances these demands for any given application is the great challenge in tire design.

Porsche designs and manufacturers some of the highest performance vehicles in the world. Because of the integral role that tires play in vehicle performance, Porsche has integrated tire development throughout their process of vehicle development. To be an Original Equipment tire provider on a Porsche vehicle or be approved by Porsche for the replacement market requires the joint product development efforts of the tire engineers working alongside the Porsche vehicle engineers.

The focus in recent radial tire development for Porsche vehicles has primarily included optimum handling on dry surfaces and the safest possible behavior on wet surfaces, even at high speeds. Tires developed by various manufacturers, in concert with Porsche, offer a specific set of wet grip properties which few, if any, other automobile manufacturers demand in equal measure from the tires they use on their vehicles.

Tires may be specified for a particular vehicle or range of vehicles and must successfully pass the tire company's laboratory tests to assure that they would be capable of adequately supporting the Porsche vehicle while allowing it to reach its top speed on the German Autobahn. Additional laboratory, test track and race track tests are conducted to confirm that the prototype tires meet Porsche's noise, hydroplaning and handling requirements. Prototype tires will also be evaluated to assess their high-speed durability, uniformity and serviceability. Upon test completion, the tires will be released for production.

Production tires that have passed all of the tests and received the engineering department's release can be branded with an N-specification. The N-specification brandings include: N-0 (N-zero), N-1, N-2, N-3 or N-4. These markings on a tire's sidewall clearly identify them as approved by Porsche for their vehicles. The N-0 marking is assigned to the first approved version of a tire design. As that design is refined externally or internally, the later significant evolutions will result in a new generation of the tire to be branded with N-1, N-2, N-3, etc., in succession. When a completely new tire design is approved, it receives the N-0 branding and the succession begins again.

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 permissible.

Tires should be replaced no less than in pairs on one axle at a time. Only tires of the same tire make and type must be used. However, in case of tire damage such as cuts, punctures, cracks or sidewall bulges that cause a single tire to be replaced for safety reasons, the remaining matching tire on that axle must not exceed 30 percent wear. If the remaining tire has more than 30 percent wear from new, it should also be replaced. Handling inconsistencies may result if this is not done.

Initially, new tires do not offer their full traction. Drivers should therefore drive at moderate speeds during the first 60-100 miles (100-200 km). If new tires are installed on only one axle, a noticeable change in handling occurs due to the different tread depth of the other tires. This happens especially if only rear tires are replaced. However, this condition disappears as new tires are broken in. Drivers should adjust their driving style accordingly.

NOTE: The last two paragraphs are excerpts from recent Porsche vehicle owner's manuals.

More Tire Tech Information


Related Links:
Original Equipment (OE) Tires
Original Equipment Tire Designations

 

Quite interesting, thank you.

To play devils advocate, has anyone changed all of their tires to non-N rated tires and noticed a difference?

 

While I can't find fault with most of what is in that post, I think the quoted paragraph needs some supporting documentation. i.e. - some actual examples of how the N rated variant of a tire differs from the generic version. Show me how the N rated version grips and stops better than the generic on a Porsche car. Show me the additional performance to support the additional cost.

My main question about this is why an N rated tire gets the same 'model' name as the non N rated version? Why have a P Zero or PS3 with an N rating if they are substantially different? Why not just call them Porsche Tires or something less confusing?

Sorry, I still need to be convinced of the differences. Coming from the company that really knows how to squeeze profit from anything, can you blame me for being suspicious?

 

Exactly! I too am suspicious that it is all fanciful bullship for "how can we get more money out of you?"

 

Still doesn't address the flat tire problem.

For those of you have owned cars without any spare in the past what do you do when you get a flat?

Living in LA, this could turn out to be a HUGE pain in the butt.

 

It sux basically - I carry a spare now, but I don't know if that is possible for the 991 - wheels getting larger - the can of goop option is wishful thinking at best. And Roadside Assist can be a drawn our ordeal if you are not close to any dealerships when you have a flat. I have lived it - not fun at all.

 

Long story short, if you get a flat after the dealerships operating hours than you have to tow the car home and wait until the next business day?

That is not going to be fun at all! Good thing these cars come with run flats and tire pressure monitors. I will be monitoring my tires very closely and won't be taking any chances and have to deal with that hassle.

 

I don't remember reading that anywhere, do they really come with run flat tires?

ChuckJ

 

I could be/most likely am mistaken. I assumed they were run flats but don't have any facts to back it up. My apologies.

 

I really liked having the run flats with my bmw, I had 3 flat tires in five years, and no worries at all, I just kept driving till it was convenient to get the tire replaced. The 991s, do not have run flats, probably because run flats are not the best for performance or that they would be too loud in 20 inch form.