Firestone announced in the offseason that for all street courses this year, the softer alternates would be constructed with a sidewall made from the sustainable guayule desert shrub. These green sidewalled tires made their debut at last year’s race in Nashville, and have been brought onboard for all five of the temporary tracks on the 2023 IndyCar schedule.
At the season-opener in St. Petersburg last weekend, there was a notable difference in the performance of the two tires, something that the best drivers and the series have regarded as a big help in improving the quality of the racing. Thanks to a mix of strategies, that is how things transpired on track.
Asked if the ‘green’ tires had behaved notably differently from the red-sidewalled alternates used at St. Pete in 2022, Krstolic told Motorsport.com: “There was not any appreciable difference in sidewall compound but of course when you build year to year there may be slight variations because you’re building with different batches of polymers and carbon and ingredients that go into the tires themselves.
“When we went to do our compound metrics that we send out to the race teams we noted that there would be a little more wear than what we’ve had in the past at St. Pete, just in the compound, nothing to do with the guayule that goes into the sidewall.
“We talk to IndyCar after every race and at the end of the year and we also get feedback from each team, and hopefully each driver after every race. And then really we’re talking with Jay [Frye, series president] and his team about what they want in terms of race quality. When they look at race quality, they look at the number of passes, number of passes for the lead – a lot of different metrics. And the one thing that gives IndyCar a good show is to have a good gap between the primary and the alternate tires.
“Certainly what we saw at St. Pete last weekend is that we had a pretty good gap between the two compounds, and drivers discovered in the Sunday morning warm-up that their alternates would wear fast if they tried to run a set that had been used very hard in qualifying.
“Romain Grosjean did a phenomenal job getting to run 28 green-flag laps on the alternates, but if you overuse them, if you put too much steering into them, too much braking into them, they’re not going to last quite as well. So whether it’s an alternate tire at a road or street course or an oval tire where we’re hoping to have a lot of degradation to help provide some racing strategic options, they really reward a good driving style –not over-slip them, not lock them up.
“We haven’t gotten all of the feedback yet from all the drivers, but from what we’ve heard so far, it seemed to give the drivers a good chance to get some different race strategies going on, and everything we’ve heard from IndyCar so far has been positive.”
One particularly interesting project is set for August, when Firestone will bring two compounds to an oval, namely WorldWide Technology Raceway at Gateway, with drivers obliged to run both compounds come the race. However, Krstolic says the task isn’t a major trip into the unknown, since both compounds have been used at the 1.25-mile oval in the past. The purpose of bringing two compounds is to allow strategists and drivers to be more creative and, hopefully, generate more passing due to the different properties of the rubber available.
“We’ve seen it’s difficult to create passing opportunities at Gateway, and we came up with a plan and presented it to IndyCar,” said Krstolic. “We’ve been talking to the race teams about this for a couple of years.
“It’s something IndyCar is pretty excited about and the race promoter is also pretty excited about, and providing not everyone runs the same strategy at the same time, it should create some extra interest in the race.
“There’ll be one set of tires that the teams can use during practice. They’ll qualify on the primary or standard tire, and then in the race they’ll have one set of tires that will be option tires.
“Now the compounds they use will not be drastically different from compounds they’re raced there in the past, – but one will be on the more durable side of what we’ve raced there in the past, and the other will be on the softer side of what we’ve taken there.
“So it won’t be too outside the box: they’ll be different enough to not just be a gimmick, but not so different that they will change the setup of the cars.”
