As quoted from Porsche manuals:
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.
Tires are your car’s only contact to the pavement.
Porsche has a special tire approvals and designation called “Porsche N-Specification”
Due to types of drivers, engine placement, weight distribution and engine power the Porsche car has to “stick to the road.” Everything about how the car rides on the pavement makes the tires choice the foundation to a valid solution. Tire design, complex materials in the tires, size, width, how it fits into the wheel well and on the wheel all becomes factors. As a world class high performance vehicle, tire development requires the provider to be approved. Specifications also joint effort with the Porsche vehicle engineers for original or replacement market.
Requirements for dry and wet surfaces must meet criteria that supersedes other automobile manufactures. The wet grip properties raise the tire performance bar at extreme levels and must result in primal optimum handling for radial tires. High speed performances must also meet at intense levels.
Tires used on Porsche has the expectation to handle speed and endurance experienced on the German Autobahn. The is also a confirmation that added laboratory, race track and test track performance be conducted to benchmark noise, handling, and hydroplane. The added expectations need tires to meet high-speed durability, uniformity and serviceability. It is only when high marks are achieved may tires that go on a Porsche be released for production for a range of cars.
Production tires that have passed all the tests and received the engineering department’s release can be branded with an N-specification. The N-specification branding include: N-0 (N-zero), N-1, N-2, N-3 or N-4. These markings on a tire’s sidewall clearly show 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.
by Tire Rack.
When in the market for new tires, realize that the designers account for a special car performance. Never underestimate your car or its potential performance.
In repairing tires due to finding nails in them. There are 2 schools of thought. First of all, never pull the nail out yourself. EVERY CASE IS DIFFERENT!!!! YOU MUST SEE A TIRE PROFESSIONAL
1. Patch whenever possible. Patch requires that the tire is removed from the car, and then the tire pulled off the rim. From inside this tires, one might patch.
2. Plugging! Plugging is a good option, but know that patching is a better option. The consideration completely depends on where a nail ends up in the tire. If a found nail might be found anywhere near the edge of a tire, the size constraint on the patch will prevent installation without carving the interior wall of the ire. In these cases.. use the plug option. If you tires need alignment, and you have plugs near the sidewalls of a tire, that plug could work its way out.
If the tire is old, and need of replacement… get new tires.