Sports car tyres make a major contribution to the ability of high-performance sports to “stick to the road”. These tyres 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 tyre design.
Porsche manufacturers and designs some of the highest performance vehicles in the world, as a result tyres play an integral role in vehicle performance. Porsche has integrated tyre development throughout their process of vehicle development. To that extend to be an Original Equipment tyre provider on a Porsche vehicle or be approved by Porsche for the replacement market requires the joint product development efforts of the tyre engineers working alongside the Porsche vehicle engineers.
Not all Production tyres make the grade and fort those 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 etc. These markings on a tyre’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 tyre design. As that design is refined externally or internally, the later significant evolutions will result in a new generation of the tyre to be branded with N-1, N-2, etc, in succession. When a completely new tyre design is approved, it receives the N-0 branding and the succession begins again. Recently N has been updated to NA for all new tyres with the designation NF used for the all-electric models.
Research and Development
The focus in recent radial tyre development for Porsche vehicles has included optimum handling on dry surfaces and the safest possible behaviours on wet surfaces, even at high speeds. Tyres developed by various tyre manufacturers, in conjunction with Porsche, offer a specific set of wet grip properties which few, if any, other automobile manufacturers demand in equal measure from the tyres they use on their vehicles. Tyres may be specified for a particular vehicle or range of vehicles and must successfully pass the tyre company’s laboratory, track and race tests to assure that they would be capable of adequately supporting the Porsche vehicle. Approval testing ensures tyres can reach their top speed on the Autobahn whilst meeting Porsche’s noise, hydroplaning, high-speed durability, uniformity, serviceability and handling requirements.
It is recommended that only matching tyres be used on Porsche vehicles. Since many Porsche vehicles are fitted with differently sized tyres on their front and rear axles, this means matching the tyre make, tyre type and N-specification. If a vehicle was originally delivered with N-specification tyres that have been discontinued and are no longer available, it is recommended to change all four tyres to a higher numeric N-specification design appropriate for that vehicle. Mixed tyre types are not recommended. Tyres should be replaced no less than in pairs on one axle at a time. Only tyres of the same tyre make and type must be used. However, in case of tyre damage such as cuts, punctures, cracks or sidewall bulges that cause a single tyre to be replaced for safety reasons, the remaining matching tyre on that axle must not exceed 30 percent wear to the other axle tyre. Otherwise, both axle tyres need replacing, as handling inconsistencies may result if this is not done.
Brand new tyres do not offer their full traction during the first 60-100 miles, therefore drivers should therefore drive at moderate speeds in order to bed in new tyres. If new tyres are installed on only one axle, a noticeable change in handling occurs due to the different tread depth of the other tyres. However, this condition disappears as new tyres are broken in. Drivers should adjust their driving style accordingly. It is also important to know that while Porsche N-specification tyres have been fine tuned to meet the specific performance needs of Porsche vehicles, the tyre manufacturers may also build other tyres featuring the same name, size and speed rating as the N-specification tyres for non-Porsche applications. These tyres 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 tyres. Using tyres that are not N-specific is not recommended and mixing them with other N-specification tyres is not permissible.