Michelin Pilot Sport 4S derived from Formula E
BY DANIEL DEGASPERI | 1st May 2017
Speaking with GoAuto at the international media launch of the Pilot Sport 4S in Abu Dhabi last week, Michelin engineering support and operational marketing manager Charles Donahoe explained that the advent of the all-electric Formula E racing regulations permitted only one tyre design to be used, in the wet or dry.
This road-like configuration helped, he said, with the design of this new tyre.
“They (Formula E) didn’t want all the tyre options,” he started.
“At motorsport events you bring three times the number of tyres that you need, then it’s a wet race and you hardly use any tyres at all. For Formula E, they wanted just one tyre option, whether it was wet or dry, hot or cold, one tyre.
“We’ve got five different tread compounds for our (Michelin) racing tyre (but) the challenge for our Formula E is to come up with a tread compound that is going to work in a wider operating window. We’re dealing with a compromise, but the tyre deals with it very well.
“This (Formula E tyre) was designed over four years ago (and) we take a lot of the design cues we developed for Formula E through to the Pilot Sport 4S. It really is helping deliver those two performance characteristics that we’re trying to overcome.”Mr Donahoe claimed that Michelin continues to be the only high-performance tyre brand to use a “bi-compound” design, the production of which can allow a softer compound to be used on the edge of the tyre and a harder variety inside.
“I’m not aware of any competitor that offers the same (bi-compound) technology in car tyres (and) it’s the same with our (flagship) Pilot Sport Cup 2,” he said.
“In terms of that compromise that some of the other tyre manufacturers are forced to do, we try to maintain strength in every area. Just through the tread design, it actually has those two (dry and wet) personalities.
“In a straight line, during hard acceleration you need a hard compound in the middle of the tyre, the same with braking. But when you corner you need a softer compound on the shoulder. We’ve used this approach with our Pilot Sport 4S.
“We have so many different compounds that go into making a tyre that we really do have a ‘chef’ basically coming up with new recipes. We’ll make the mix and then test pads, and we can understand a lot about the properties of the rubber without building a tyre. We can simulate exactly how the tyre would function.”Michelin has claimed a one-metre improvement in wet and dry braking with the Pilot Sport 4S compared with 2010’s Pilot Super Sport, owing predominantly to the tyre compound improvements but also tyre construction methods that allow improved heat dissipation.
“If you have a temperature difference of more than 15 degrees across the tyre, you perhaps have too aggressive a (suspension, camber, toe-in) setup for race distance,” Mr Donahoe explained, while adding that it was an especially important factor when buyers are “targeting around 40,000km” from a tyre set.
“You end up working a part of the tyre on one side a lot more than the other side. We faced some of that with the architecture of the Super Sport, not a huge problem, but if you are going to influence the wear life of that tyre you have to manage the distribution.
“We’ve managed to (with Pilot Sport 4S) eliminate areas of high pressure, for more even distribution, for increased wear life.”As an original equipment (OE) fitment to new cars, the Pilot Sport 4S will make its debut in the Mercedes-AMG E43 and E63, and Ferrari GTC4 Lusso and will be available only in 19- and 20-inch diameter – although the company will add an 18-inch option in 2018.
According to Michelin, the Pilot Sport 4S is 80 per cent on-road focused and 20 per cent track focused, and is aimed at owners of the BMW M4, for example. It is placed one rung below the Pilot Sport Cup 2 that is an 80 per cent track tyre with 20 per cent on-road and targeted at M4 GTS buyers.
Replacing the Pilot Super Sport name with Pilot Sport 4S was also designed, according to Michelin Australia marketing manager Tim Hoare, to allow buyers to more obviously know they are stepping up from its entry performance tyre, the Pilot Sport 4.
The Pilot Sport 4S will not, however, be a markedly more expensive tyre than the one it replaces.
“From a price perspective the area we will focus is around there not being an increase over the Pilot Super Sport,” he said.
“The Pilot Sport Cup 2 will remain the halo product, but what we will try to do… we had a little bit of confusion before. We had the Pilot Sport 3, and a Pilot Super Sport and in some sizes the price jump was significant.
“By removing the Super Sport name in effect outside of a few sizes for OE, having that we think reduces a bit of the confusion so we can have a much more uniform offer with Pilot Sport 4 and Pilot Sport 4S and Pilot Sport Cup 2.”
