Firestone's new alternates prove to be exactly what the doctor ordered

The IndyCar Series asked Firestone to create a wider separation in performance between its primary and alternate tires, and according to two of the series’ best drivers, it’s mission accomplished and then some.

Firestone's alternate tires featuring renewable guayule rubber on the green-banded sidewalls were a quick-burst revelation.

“Man it’s interesting,” Andretti Autosport’s Kyle Kirkwood told RACER after leading Friday’s running. “Those green tires, they’re not going to last. It’s going to shake some things up this weekend, for sure.”

Kirkwood was amazed at how quickly the alternates switched on, and how swiftly they turned off.

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“They did it! They definitely created some separation,” he said with a laugh. “It’s like you’ve got tire warmers on; it’s pretty immediate. When you drive out of the pits, you’re like, ‘Wow, these have a lot of grip.’ And they definitely do. It’s a lot gripper than what we had last year.”

Chip Ganassi Racing’s Scott Dixon expects pit stop strategies to change on Sunday due to the peaky performance and wear.

“I think both tires come in super quick,” he said. “The greens for sure, in immediately. It seems like most of the quick times were done on the first lap. They’ve done a good situation here and I think the deg (tire degradation) is going to be super high on the greens. I think it will not be an easy two-stopper; it’s automatically going to go to a three-stopper just because you’re not going to be able to get the miles out of your greens.

“The primaries, for me, deg’d pretty hard as well. It looked like the same for most, so I think there’s going to be a clear divide between the cars that sorted it out. It’s going to be great racing.”