Scott Dixon once again found himself on the top of the timesheets on day four of Indianapolis 500 practice.
The veteran upped his average speed to 233.302 on his fastest lap, and continued the trend of Chip Ganassi Racing looking like the team to beat this year.
Just behind him was Colton Herta, who improved greatly from his previous running to put in the second fastest lap of the day.
The track was hot and slippery and the winds were gusty at times, with many drivers reporting that finding a balance through all four corners was difficult.
Conditions were largely representative of the predicted weather for the weekend, so it was more important than ever for the drivers to fine-tune their setups to suit their driving style.
More boost means more speed
Today was the first day that the teams were allowed to increase the pressure of their turbo boost systems up to their full capacity.
The higher boost pressures are allowed for qualifying only, and give the drivers close to 10 extra miles per hour of speed around the circuit.
The plan for most teams was to start with a higher level of downforce and slowly trim that out until each driver was right at the edge of comfort at the high speeds.
With close to 700 HP at their disposal, a full 24 drivers were able to set fast laps over 130 MPH by the end of the day.
Colton Herta had the fastest speed trap reading of the afternoon with 240.359 MPH being recorded at the end of the back stretch.
On the other end of the scale, new entry Top Gun Racing could only muster a 226.055 MPH average on their fast lap. The team will have to find some extra speed tomorrow in order to make the 33-car cut.
Four critical laps
In contrast to other events, the grid for the Indy 500 is set by an average of four consecutive flying laps.
Teams were practicing putting complete runs throughout the day to simulate the qualifying runs they all will be taking tomorrow.
On the charts of those all-important four-lap average speeds, it was Marcus Ericsson whose average lap speed was 231.949 MPH.
Andretti Autosport looked really strong in qualifying trim, as opposed to the struggles they had climbing the charts over the past few days, and placed three drivers in the top five spots of the four-lap averages.
Rahal Letterman Lanigan Racing looked to have their cars dialed in as well, including Santino Ferruci who bounced back from a crash yesterday to put himself in the top 10.
Tomorrow there is another short practice session, but then qualifying begins in the afternoon when all but the first three rows will be locked in.
The full list of single-lap times can be found below:
| # | Driver | Time | Speed (MPH) | Gap (seconds) | Laps |
|---|---|---|---|---|---|
| 1 | Scott Dixon | 00:38.5766 | 233.302 | –.—- | 29 |
| 2 | Colton Herta | 00:38.6624 | 232.784 | 0.0858 | 34 |
| 3 | Tony Kanaan | 00:38.6781 | 232.69 | 0.1015 | 26 |
| 4 | Marcus Ericsson | 00:38.7045 | 232.531 | 0.1279 | 39 |
| 5 | Alex Palou | 00:38.7672 | 232.155 | 0.1906 | 23 |
| 6 | Pato O’Ward | 00:38.7874 | 232.034 | 0.2108 | 30 |
| 7 | Alexander Rossi | 00:38.8160 | 231.863 | 0.2394 | 40 |
| 8 | Takuma Sato | 00:38.8604 | 231.598 | 0.2838 | 28 |
| 9 | Ed Jones | 00:38.8653 | 231.569 | 0.2887 | 18 |
| 10 | Ryan Hunter-Reay | 00:38.8703 | 231.539 | 0.2937 | 33 |
| 11 | Graham Rahal | 00:38.8738 | 231.518 | 0.2972 | 30 |
| 12 | Rinus VeeKay | 00:38.9063 | 231.325 | 0.3297 | 18 |
| 13 | Stefan Wilson | 00:38.9650 | 230.977 | 0.3884 | 28 |
| 14 | Santino Ferrucci | 00:38.9739 | 230.924 | 0.3973 | 21 |
| 15 | Ed Carpenter | 00:38.9777 | 230.901 | 0.4011 | 29 |
| 16 | Jack Harvey | 00:38.9880 | 230.84 | 0.4114 | 35 |
| 17 | James Hinchcliffe | 00:38.9919 | 230.817 | 0.4153 | 30 |
| 18 | Pietro Fittipaldi | 00:39.0174 | 230.666 | 0.4408 | 17 |
| 19 | Conor Daly | 00:39.0241 | 230.627 | 0.4475 | 36 |
| 20 | Felix Rosenqvist | 00:39.0308 | 230.587 | 0.4542 | 36 |
| 21 | Helio Castroneves | 00:39.0435 | 230.512 | 0.4669 | 48 |
| 22 | Josef Newgarden | 00:39.0491 | 230.479 | 0.4725 | 48 |
| 23 | Max Chilton | 00:39.0501 | 230.473 | 0.4735 | 47 |
| 24 | Scott McLaughlin | 00:39.0600 | 230.415 | 0.4834 | 30 |
| 25 | Juan Pablo Montoya | 00:39.0683 | 230.366 | 0.4917 | 44 |
| 26 | Marco Andretti | 00:39.0735 | 230.335 | 0.4969 | 25 |
| 27 | Dalton Kellett | 00:39.0970 | 230.197 | 0.5204 | 20 |
| 28 | JR Hildebrand | 00:39.1351 | 229.973 | 0.5585 | 36 |
| 29 | Will Power | 00:39.1564 | 229.847 | 0.5798 | 42 |
| 30 | Simon Pagenaud | 00:39.1658 | 229.792 | 0.5892 | 41 |
| 31 | Sage Karam | 00:39.2095 | 229.536 | 0.6329 | 43 |
| 32 | Simona De Silvestro | 00:39.2197 | 229.477 | 0.6431 | 34 |
| 33 | Sebastien Bourdais | 00:39.2284 | 229.426 | 0.6518 | 23 |
| 34 | Charlie Kimball | 00:39.3839 | 228.52 | 0.8073 | 30 |
| 35 | RC Enerson | 00:39.8134 | 226.055 | 1.2368 | 33 |
