Scott Dixon, the 2008 Indianapolis 500 winner, had the fastest car in Thursday's Day 5 practice session at the Indianapolis Motor Speedway, but things get more serious on Friday when vehicles will be packed with more power.
IndyCar approved an increase of the turbocharger boost level for Friday, which is being dubbed "Fast Friday." It will add about 40-50 horsepower and increase speeds about 4-5 mph per lap.
"It's kind of like starting over," Bill Pappas, lead engineer for Justin Wilson's Honda-powered vehicle, told IndyCar.com.
Wilson recorded a speed of 221.715 mph on Thursday, but Dixon had the fastest car on Thursday, turning in a lap time of 40.3428 seconds and a speed of 223.088 mph. That's the second fastest time of the month.
Josef Newgarden, who had the fastest time in three of the four previous days of practice, had the second fastest time on Day 5 of practice, 222.709 mph. Graham Rahal was third-fastest at 222.080, and Will Power was next at 221.932. Wilson was next, as 16 drivers surpassed 220 mph on Thursday.
Friday is the final day of practice at the 2.5-mile track, with qualifying for the Indy 500 starting on Saturday. The Indy 500 is scheduled for May 27.