Goodyear’s ultra-ultra high-end performance tyre, the new Eagle F1 Supersport RS has been given the green light by Porsche to become one of the factory tyres on its range-topping 911 GT2 RS for all new deliveries, marking what will be the beginning of the American brand’s assault on the high-end supercar segment with original equipment tyres.
Having launched its new range of Supersport tyres as part of the Eagle F1 family, the new Supersport R (Michelin Pilot Sport Cup 2 equivelants) and Supersport RS (Michelin Pilot Sport Cup 2 R equivalents) are heading to Australia from May, however the RS tyre is currently only available in sizes for the GT2 and GT3 RS 911s.
Speaking to CarAdvice at the launch of the Supersport range at the Ascari racetrack in Spain this week, one of the company’s tyre construction engineers, Nicolas Lhenry, confirmed that Porsche has approved its range-topping RS tyre to co-exist with the Michelin Cup 2s.
Interestingly, the Supersport R (which sits below the RS) is already faster than the Cup 2 around both the company’s testing facility in Spain and the Nardo race track in Italy, according to Lhenry.
“When we do the evaluation, [Supersport R and RS] is faster [than the Michelin equivelants],” Lhenry said.
“The requirements from Porsche [are a lot], especially from the Supersport RS, there we are approved, the next [GT2 RS] cars that will come out of Porsche factories will be [wearing] RS [tyres].”
Meanwhile, he also confirmed that around a race track like Ascari or Nardo in Italy there is a 2.5- to 3-second difference in performance between the Supersport R and RS tyres from Goodyear (fitted to a GT2 RS).
“The structure is quite the same, the difference is mostly in the compound. It’s the different way we mix and blend it, we mix it with additives, with this R we have traction resin and for the RS we have a different kind, different grades. Like natural rubbers, you have different classes and purities.”
Lhenry said that while it takes robots roughly one minute to make a tyre, the curing and other complications of the softer RS tyre make it a more difficult item to produce. Though he admitted that it’s not necessarily more expensive from a raw material cost.
“[The RS is] harder to make, it’s more advanced technology. If you look at the side walls the treadwear (UTQG) is the same – 80 for both – it's explained by RS having a softer compound. The surface area is higher for RS – more material but lower depth. What you gain by surface, you lose by depth.”
The 80 treadwear rating is significantly different to the 180 for the Michelin equivalent (Cup 2s) but differs to the 40-140 range that Michelin will sell its new Cup2 R tyres.
The difference between the R and RS tyres in terms of compound comes down to the type of rubber used and also the amount of surface area offered, with the RS having significantly more surface area but actually being thinner (so both the R and RS use similar amounts of material, just of a different kind).
Goodyear did not have any data to share about its internal valuation regarding any comparisons to Pirelli equivalents such as the Trofeo and Trofeo R. The company was also reluctant to allow us to test the high-spec RS tyre, only giving us access to the R (in a GT3 RS) for now.
For those keen on ordering a set of RS tyres, you may have a fair wait until the sizes become more readily available unless you own a GT2 RS, and even then it’s likely that Goodyear will keep its most track-focused road legal tyre for supercars only.
“The line-up is going to evolve, to which direction I cannot tell you, but it will be expanded to the really high-end supercars.”
The main challenges for the development remained operating temperatures to meet road legal requirements.
“The difficulty for such a tyre is to warm up, if you want to go to the track with your GT2 RS, your tyre is cold from the garage and it needs to respond immediately. The team from compounding had a huge job, to make them work at low temperatures.”
The Supersport R and RS will find their sweet spot at around 90-100 degree tyre temperature, but the RS will be able to maintain its optimal operating window for significantly longer around a race track.
Although there is no official mileage target with either tyre, we are told that they will easily last 150 laps of a 3-4km race track before showing signs of noticeable performance degradation.
Check back soon for our full review of the Goodyear Supersport range.