Sebastien Bourdais has set the benchmark on ‘Fast Friday' at Indianapolis, while Fernando Alonso was fourth fastest for the third day in a row.
With cars in qualifying trim ahead of Saturday's first day of qualifications, including an extra 10kPa of turbo boost, Bourdais lapped the 2.5mi superspeedway in 38.6074s (233.116mph, 375.164km/h) during the first half-hour of the day.
The Dayle Coyne Honda driver's effort bested that of Ryan Hunter-Reay, who had set a 38.7711s within the first 10 minutes of the session in his Andretti Autosport Honda.
Hunter-Reay remained second for the duration, while the top two were reversed on the non-tow rankings.
Another two Andretti entries followed, with Takuma Sato third-fastest.
Unlike most of the front-runners, Alonso's fastest lap in the McLaren-backed Honda came in the final hour of the day, and in a good sign for qualifying was the first of four consecutive laps above 231mph.
Rain had threatened and ultimately cost drivers more than two-and-a-half of the six hours of scheduled running, hence the early rush to set lap times.
Juan Pablo Montoya led the Chevrolets for Team Penske in fifth, while team-mate Will Power was 16th.
Spencer Pigot (Juncos Racing Chevrolet) and Zach Veach (AJ Foyt Racing Chevrolet) came to grief at Turns 1 and 2, respectively, but neither was injured.
Saturday sees a further 90 minutes of practice from 2200 AEST before Day 1 of qualifications starts at 0100 (Sunday morning) AEST.
VIDEO: Pigot hits the wall
VIDEO: Veach hits the wall
Practice 5: Indianapolis 500
Pos | Driver | C/A/E/T | Time | Diff | Gap | Best lap | Total laps |
1 | Bourdais, Sebastien | D/H/H/F | 00:38.6074 | 11 | 30 | ||
2 | Hunter-Reay, Ryan | D/H/H/F | 00:38.7711 | 0.1637 | 0.1637 | 3 | 21 |
3 | Sato, Takuma | D/H/H/F | 00:38.7983 | 0.1909 | 0.0272 | 4 | 23 |
4 | Alonso, Fernando (R) | D/H/H/F | 00:38.8220 | 0.2146 | 0.0237 | 36 | 46 |
5 | Montoya, Juan Pablo | D/C/C/F | 00:38.8463 | 0.2389 | 0.0243 | 5 | 17 |
6 | Hinchcliffe, James | D/H/H/F | 00:38.8740 | 0.2666 | 0.0277 | 10 | 38 |
7 | Aleshin, Mikhail | D/H/H/F | 00:38.8858 | 0.2784 | 0.0118 | 10 | 37 |
8 | Howard, Jay | D/H/H/F | 00:38.9181 | 0.3107 | 0.0323 | 4 | 36 |
9 | Jones, Ed (R) | D/H/H/F | 00:38.9185 | 0.3111 | 0.0004 | 8 | 23 |
10 | Rossi, Alexander | D/H/H/F | 00:38.9288 | 0.3214 | 0.0103 | 23 | 25 |
11 | Kanaan, Tony | D/H/H/F | 00:38.9519 | 0.3445 | 0.0231 | 3 | 30 |
12 | Dixon, Scott | D/H/H/F | 00:38.9584 | 0.3510 | 0.0065 | 16 | 29 |
13 | Castroneves, Helio | D/C/C/F | 00:38.9640 | 0.3566 | 0.0056 | 3 | 44 |
14 | Servia, Oriol | D/H/H/F | 00:38.9801 | 0.3727 | 0.0161 | 8 | 40 |
15 | Andretti, Marco | D/H/H/F | 00:39.0000 | 0.3926 | 0.0199 | 43 | 45 |
16 | Power, Will | D/C/C/F | 00:39.0088 | 0.4014 | 0.0088 | 22 | 24 |
17 | Carpenter, Ed | D/C/C/F | 00:39.0097 | 0.4023 | 0.0009 | 11 | 28 |
18 | Chilton, Max | D/H/H/F | 00:39.0225 | 0.4151 | 0.0128 | 4 | 33 |
19 | Hildebrand, JR | D/C/C/F | 00:39.0241 | 0.4167 | 0.0016 | 3 | 22 |
20 | Kimball, Charlie | D/H/H/F | 00:39.0735 | 0.4661 | 0.0494 | 9 | 41 |
21 | Mann, Pippa | D/H/H/F | 00:39.1130 | 0.5056 | 0.0395 | 2 | 28 |
22 | Rahal, Graham | D/H/H/F | 00:39.1292 | 0.5218 | 0.0162 | 8 | 34 |
23 | Pagenaud, Simon | D/C/C/F | 00:39.1350 | 0.5276 | 0.0058 | 11 | 17 |
24 | Newgarden, Josef | D/C/C/F | 00:39.3660 | 0.7586 | 0.2310 | 34 | 36 |
25 | Harvey, Jack (R) | D/H/H/F | 00:39.4001 | 0.7927 | 0.0341 | 22 | 23 |
26 | Karam, Sage | D/C/C/F | 00:39.4462 | 0.8388 | 0.0461 | 30 | 38 |
27 | Munoz, Carlos | D/C/C/F | 00:39.4813 | 0.8739 | 0.0351 | 9 | 24 |
28 | Daly, Conor | D/C/C/F | 00:39.6083 | 1.0009 | 0.1270 | 31 | 42 |
29 | Chaves, Gabby | D/C/C/F | 00:39.6182 | 1.0108 | 0.0099 | 36 | 37 |
30 | Veach, Zach (R) | D/C/C/F | 00:39.6333 | 1.0259 | 0.0151 | 41 | 52 |
31 | Saavedra, Sebastian | D/C/C/F | 00:39.7835 | 1.1761 | 0.1502 | 14 | 27 |
32 | Pigot, Spencer | D/C/C/F | 00:39.7931 | 1.1857 | 0.0096 | 16 | 20 |
33 | Lazier, Buddy | D/C/C/F | 00:40.9761 | 2.3687 | 1.1830 | 22 | 30 |
(C)hassis: D=Dallara | (A)erokit: C=Chevy, H=Honda | (E)ngine: C=Chevy, H=Honda | (T)yre: F=Firestone