Felix Rosenqvist, Scott McLaughlin reach the top of Indianapolis 500 speed charts on Fast Friday

Rosenqvist posted the fastest lap of the day, 233.372 mph though it came with a tow, and the fastest four-lap average, 232.828 in the final practice before qualifying. But it was McLaughlin who waited through the two-hour rain delay and two more hours of inactivity before turning heads with the fastest no-tow lap of the week, 232.674, and the second fastest four-lap average, 232.572.

It sets up a potentially dramatic qualifying weekend between the New Zealander who won Indy's pole in 2024 and Rosenqvist, who will try to put Meyer Shank Racing on the front row.

“It was better than going upside down, that was the last time I was here on this boost level," McLaughlin said after finishing his day with three hours of practice time still left. “I think we got a really good test point for the team and we'll go back, scratch our heads a little bit more. But it's just going to get harder as the weekend goes on.”

The only other driver with a faster lap than McLaughlin was Alexander Rossi with a 232.93. Rossi and McLaughlin both changed engines earlier this week because of mechanical problems.

Penske's cars were so dialed in that McLaughlin and his teammates — two-time Indy winner Josef Newgarden and David Malukas, last year's Indy runner-up — logged the fewest laps of any team after IndyCar officials gave each driver an additional boost of about 100 horsepower.

But most of the 33 drivers attempting to make the traditional starting grid for the May 24 race recognize things could change quickly Saturday.

Rain is in the forecast for the first four scheduled hours of qualifying. If it stays dry for the final three hours, the weather conditions could be quite similar to what they had Friday. Then it's expected to heat up substantially Sunday, causing even more changes.

“It's going to get hotter, a bit of rain coming in as well, so we've just got to make every run count,” McLaughlin said, who got a boost by drawing the No. 6 spot in the qualifying line — ahead of Rosenqvist at No. 11, Rossi at No. 20 and points leader Alex Palou at No. 31. “I felt like that was my best run of the weekend, so really happy to do that at that (increased) boost level.”

What else could be in play? New strategies to comply with the revised qualifying format.

Race organizers have eliminated the last row shootout because there are only enough driver-car combinations to fill the traditional 33-car starting grid, meaning none will be bumped.

Instead, there's a new wrinkle in pole qualifying. The fastest 15 cars will advance to Sunday's round with the top nine locked into the 12-car pole shootout and the other six vying for the final three spots. The six fastest cars in Round 2 will compete to determine the pole winner.

“Our goal is to be solidified in the top nine, to be honest,” Andretti Global driver Kyle Kirkwood said. “I think that’s probably everyone’s goal. You know, in the past couple of years we’ve had chances to be at the front and it just kind of hasn’t materialized when Saturday comes along, but I think this year feels a little bit different.”

Kirkwood is second in points heading into next weekend's race, but struggled to stay with the Fast Friday leads.

Palou, the defending 500 champ, had the second fastest no-tow lap at 23

The Spaniard who drives for Chip Ganassi Racing has won three of this season's first six races and posted the second-fastest no-tow lap Friday at 232.532.

“Qualifying sims on yesterday’s boost, I don’t want to say it’s easy, but you feel like there’s a ton of grip, like the car is not on the limit," Palou said. "Today or this weekend it’s going to feel like the car doesn’t like it, it’s not as happy, you start sliding, need to work more with your tools. You cannot go aggressive with the amount of trim you are doing.”

And it will set up a memorable qualifying weekend for one lucky driver.

“I've kind of gone through every emotion possible in the last two weeks,” Rosenqvist said, reflecting on the recent birth of his first child. “It's cool, it's kind of hard to explain and it becomes like the No. 1 coolest thing you've ever done. But I feel like a driver it kind of makes you a bit calmer, a bit more confident or a little less worried about things. You just kind of go out and drive.”

AP auto racing: https://apnews.com/hub/auto-racing