Ryan Hunter-Reay had the fastest Honda in practice on Friday at 178.379 mph, but that was 12th-fastest overall. Only one Chevrolet ran slower: rookie Stefano Coletti (177.916).NEWTON, Iowa – High speeds, high heat.That and Chevrolet’s dominance are the short summary of IndyCar’s quick trip so far to Iowa Speedway, the smallest oval of the six on the schedule.Friday temperatures soared into the mid-90s, with thick humidity. More of the same is expected Saturday, although the lateness of the Iowa Corn Indy 300’s start — 7:50 p.m. Iowa time — figures to bring relief.Sweat poured from the crew members in Friday’s two practices. The drivers said it wasn’t so bad in the car, but getting out felt like taking a bath.“In the (car), adrenaline kicks in,” last year’s champion Ryan Hunter-Reay said. “It’s when you get out that you notice the heat.”Hunter-Reay looks for a win at site of last victoryQualifying is Saturday at 4 p.m. ET. The 300-lap race is at 8:50 p.m. (NBCSN).Tony Kanaan, who has finished in the top three of the past five Iowa races, including a win in 2010, led the pack of 11 Chevrolet drivers at the top of Friday’s speed chart. His lap of 181.273 mph — that’s 17.7544 seconds around the 0.875-mile track — was one of eight above 180 mph.Hunter-Reay had the fastest Honda at 178.379 mph in 12th. The only Chevrolet driver behind him was rookie Stefano Coletti at 177.916 mph in 16th.Return to Milwaukee uncertainMichael Andretti still isn’t sure if his sports marketing company will promote another race at the historic Milwaukee Mile.“I don’t know what IndyCar wants to do,” Andretti said Friday.Andretti said he hasn’t seen final financial numbers from last week’s event, but said the size of the crowd was “definitely way more” than The Indianapolis Star’s estimate of 15,000. Andretti declined to give a figure.Thumbs up, thumbs down from the Milwaukee MileStill, there are no guarantees it will be an investment worth making in 2016, he said.“Odds are against it, but it’s not dead,” Andretti said. “We need to talk to IndyCar.”Etc.Hunter-Reay has won twice here, but he stressed he hasn’t been dominant. He led only 15 laps in winning the 2012 race and led only the final two laps last year. Those are the only laps he’s led here in seven starts. … There are 24 drivers in this field. Twelve have led laps here. … There were no accidents in IndyCar’s two Friday practices.Follow Star reporter Curt Cavin on Facebook and on Twitter: @curtcavin.