Mercedes-AMG GT Coupe Tires Took 3 Years To Develop

When the new Mercedes-AMG GT 63 Coupe debuted at Monterey Car Week last year, many were taken by its attractive exterior, the 577-horsepower V8, and the sumptuously appointed interior. But more than a year after its reveal, we’re learning about one of the more interesting (albeit less glamorous) aspects of the AMG – its tires.
 

Per the latest Tyre Reviews video on YouTube, Michelin and the automaker worked on the GT’s Pilot Sport S 5 tires for three years, fine-tuning the high-performance rubber to work perfectly with Affalterbach’s 911 hunter. According to Tyre Reviews founder and presenter Jonathan Benson, the front tires boast 25 different specs compared to a regular Pilot Sport S 5, while the rear axle has 20 differences.
 
Three Years To Make The Tire As Perfect As Possible
With three years of work – nearly as long as some cars’ development cycle – the GT-specific Pilot Sport S 5 should be pretty special. Michelin test driver Pierre-Antoine Gregoire explains that AMG wanted the best possible handling and wet performance from the tire – important in a car that can reach 60 mph in 3.1 seconds. But how did Michelin meet Mercedes’ requirements?
 
For a start, the front tire comprises three different types of rubber. Half of the tread is a High Silica Compound for maximum grip in the wet, while approximately one-third is a Carbon Black Compound for high-performance driving in dry conditions. The outer part of the tire has a High Endurance Wear Strip for track use. That’s remarkable, but so is the rear set.
 
Front And Rear Tires Use Different Compounds
For the rear axle, the High Silica Compound takes up even more real estate on the tread and features a Hybrid Silica Compound in between. This provides grip in the wet and the dry, while the Carbon Black Compound is also used for maximum performance in the dry. Gregoire notes that ‘soft’ handling was very important to Mercedes-AMG.
 
Essentially, this has to do with ‘sub-limit’ handling and is the experience that most owners/drivers will feel during day-to-day driving. The tire specialist says this accounts for around 70% of his work and deals with things such as:
– Whether the vehicle tracks straight (drives in a straight line with no interference)
– Making the dead zone as small as possible
– Steering feel
– Steering input required; does it react well?
– High-speed lane changes
 

While this took plenty of time to develop, Gregoire notes that the trickiest part of developing the GT-specific Pilot Sport S 5 was striking the perfect balance between dry and wet handling. As the AMG GT is likely to be used as both a performance car and a loping GT cruiser, Mercedes demanded exceptional handling in either environment.
 
Finding A Balance Between Wet And Dry Handling Was Tricky
You don’t need to be a tire expert to know that’s a difficult objective to achieve – that’s why most manufacturers offer their vehicles with summer and all-season tires. But Michelin and Gregoire managed to achieve this, working on the incredible rubber from the early days of the GT’s development cycle.
 
“On this project, there was a quite difficult challenge to tackle. [It] was to get good wet handling behavior without losing the good dry handling behavior, because, at one point, we had really good soft and max handling performance on dry, but on the wet, we had a balance that was making sense. But the transition between the adherence and the drift was a bit too sudden and [made] the car a bit difficult to drive. It’s very important for our customers to have easy-to-drive behavior even when you reach the limit and even if you drift somehow. This was quite hard to get.” – Pierre-Antoine Gregoire, Michelin Test Driver