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Mario Isola, Pirelli's head of car racing, says the sport's move to 18-inch tyres from 2021 is set in stone, with no backpedaling possible on the part of the teams.
Tyres have often been the target of the teams and drivers' grievances in the past few seasons, whether the criticism focused on durability or grip, or sometimes both.
Pirelli made several specification changes in the past to comply with Formula 1's requirements or its mandate to help improve the show on the track.
But when changes are met with disappointment, teams have the clout to turn around decisions, as was the case with Pirelli's 2020-spec tyres that were trialed and tested last year and eventually scrapped in favour of a status quo for this year in terms of compounds.
However, Isola is adamant that there will be no such turnabout in twelve months with regard to the sport's switch to the Italian manufacturer's 18-inch tyres.
"There is no chance of going back to the 13-inch tyres," said the Italian engineer, quoted by Motorsport-Total.
"Fortunately, we already ran three tests in 2019. The initial feedback for the 18-inch tires was good, so I don't expect any surprises this year.
"When everything is new, you usually expect a problem and that you might have to stop for half a day or more," added Isola. "But we had no problems at all."
Pirelli will continue its 18-inch test programme this year, with 25 days of testing scheduled at several venues.
But unlike 2019 when only eight teams took part in the specific tests, all ten teams will supply mule cars for Pirelli's development programme.
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