Published in the February 2014 issue of “Die Porsche Kassette”
If I had 1HP for every time that I’ve been asked about N-rated tires in a Porsche, I’d have at least a Carrera GT, a GT2 and a 918 Spyder!
Whether over the phone, by e-mail, in person or through the Internet forums I constantly get questions such as these:
“Does the N-rating (N0, N1, N2, N3, N4) really make a difference?”
“I am looking for new 18" tires for my 996 and I’m wondering if the "N" rating is still a requirement.”
“ Apparently a non-N-rated tire can make the 911 kind of squirrelly (?) to drive. Your thoughts?”
“ I understand that the rear tires of the turbos (all 996s?) wear on the inner edges faster due to camber. Do the N rated last any better?”
“ What are your thoughts on replacing the OEM N rated tires with non N rated tires?”
So, for the Nth time, here it goes:
An N-rated tire is a tire from one of various Porsche-approved tire manufacturers that has passed a series of difficult and diverse tests designed by Porsche engineers to ensure maximum performance and safety under a wide range of driving conditions.
To have this rating stamped on the side of their tires, and to be an OEM (Original Equipment Manufacturer) tire provider for Porsche requires the joint product development efforts of the particular manufacturer’s tire engineers working alongside the Porsche vehicle engineers.
In some instances specific tires will only be approved for specific Porsche applications or models.
Let’s look at some of the tests required by Porsche for N-rating approval:
• SPEED: The tire must be capable of safely handling the Porsche vehicle at any speed while allowing it to reach its top speed on a test track or on the German Autobahn.
• NOISE: As tires continue to grow in size and width, noise suppression becomes more and more important. Generally speaking, Porsche performance tires are low profile and very soft (sticky). This makes it even more difficult to manage road noise. You can rest assured that those tires with the Porsche N rating will be as quiet as possible.
• HYDROPLANING: 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.
• BRAKING: Tires must provide a quick, safe and modular deceleration from several speed benchmarks (60 mph - 0 mph, 100 mph - 0 mph and 150 mph - 0 mph) in the least amount of real estate.
• HANDLING: This particular heading doesn’t require any additional explanation. Your tires provide the grip that keeps your Porsche “stuck” to the road.
Once a tire has been approved by Porsche it is branded with the N-rating.
The N-specifications include: N0 (N-zero), N1, N2, N3 or N4.
These stamps on a tire's sidewall clearly identify them as approved by Porsche for their vehicles.
The N0 marking is assigned to the first approved version of a tire design. As that design is refined externally or internally, the subsequent significant evolutions will result in a new generation of the tire to be stamped with N1, N2, N3, etc., in succession.
Higher ratings such as N1, N2, N3, etc. do not imply speed rating increases but instead refer to the next version (with refinements) of the original design.
When a completely new tire design is approved, it receives the N0 branding and the succession begins again.
It is important to note that certain tire manufacturers may produce the exact same tire in name, size and speed rating as those that have the N spec approval.
However, if they are not stamped with the N-rating then it is very likely that they do not adhere to the same rigid production and quality requirements demanded by Porsche.
This N-rating isn’t free. It comes at a price. All of that development and testing costs the tire manufacturers and Porsche a penny or two. For instance, one of the most popular tires for a newer Porsche is the new Michelin Pilot Super Sport (Max Performance Summer) 265/35/ZR19 N0. It can be purchased from TireRack.com for $419.00 each.
The same tire, without the N0-rating but with the exact same specs is offered by TireRack.com for $297.00 each.
There are N-rated tires for all applications, such as: Summer Tires, Cold Weather Tires, All Season Tires, Off Road Tires, Track Tires, etc.
Porsche makes public a complete list of N-rated tires at:
http://www.porsche.com/usa/accessoriesandservices/porscheservice/documentsanddownloads/, but if don’t have access to this web address, just call your dealer. They can provide you with the different OEM tire suppliers and different N-rated tire options for your particular car. The Porsche-approved (N-rated) tire manufacturers are: Michelin, Pirelli, Continental, Bridgestone, Dunlop, Good-Year, Toyo, and Yokohama among a few other select suppliers. Of these manufacturers less than 5% of their production is N-rated.
You can check the tire manufacturer’s websites which should include N-rated tire information for their products.
Generally, N-rated tires can only be obtained from a Porsche dealer or TireRack.com (official tire supplier to PCNA dealers).
I have never driven a Porsche with N-rated tires where the tires have disappointed me. But I’ve also been very well impressed by Porsches shod with some non-N-rated tires.
I’ve found that most of the N-rated tires are outstanding, but the are many, many other very good, even great tires that aren’t N-rated and they offer close-to-N-rated performance at substantially lower cost.
Now, having said all that, is it necessary to run N-rated tires exclusively?
With what you now know, you’ll have to answer that one yourself.
To learn more about tires and Porsches in general, please visit my website at: wwwPedrosGarage.com.
Ⓒ2013 Technolab / PedrosGarage.com