Ryan Hunter-Reay led Marco Andretti for an Andretti Autosport one-two on the speed charts at the end of the second day of practice for the Indianapolis 500.
The 2012 series champion finished the day with a fastest average speed of 225.025mph; roughly 2mph quicker than the benchmark set by Will Power on Sunday.
Andretti's best was a 224.037mph average, with three-time Indy 500 winner Helio Castroneves just behind him at 223.635mph.
Justin Wilson and Juan Pablo Montoya rounded out the top five.
"We got a lot of work done today; a lot for what we need for the race weekend," said Hunter-Reay, who completed 113 laps.
"It was fun with my team-mates. That's the great thing about Andretti Autosport, we have five quick cars and we can all run together.
"We were getting a feel for downforce levels and race simulation running. It was fun, we got through a lot of work today and it's only Monday."
Occasional rain showers were responsible for most of the 10 caution periods that occurred during the day. The other was caused by Ed Carpenter, whose car suffered a mechanical problem.
But despite the interruptions 30 cars managed to get some track time, with last year's winner Tony Kanaan ticking off a field-high 131 laps.
"Lots and lots of running out there," said the Brazilian. "Today is only the first day of testing the primary car for the race, so we went through a laundry list of items we've been wanting to run. Overall it was a good day of learning for us."
An additional incentive for maximising running time on Monday may have been the weather forecast, which heralds the possibility of more rain in the days ahead.
The only drivers still yet to make an appearance on the track for Indy practice are James Davison, who is scheduled to begin running on Thursday, Buddy Lazier, and Sebastian Saavedra.
Pos Driver Team/Engine Speed Time Gap Laps 1. Ryan Hunter-Reay Andretti/Honda 225.025 39.9955s 113 2. Marco Andretti Andretti/Honda 224.037 40.1719s +0.1764s 88 3. Helio Castroneves Penske/Chevy 223.635 40.2441s +0.2486s 96 4. Justin Wilson Coyne/Honda 223.611 40.2484s +0.2529s 64 5. Juan Pablo Montoya Penske/Chevy 223.395 40.2874s +0.2919s 117 6. Carlos Munoz Andretti/Honda 223.172 40.3276s +0.3321s 70 7. Mikhail Aleshin Schmidt/Honda 223.120 40.3371s +0.3416s 89 8. Scott Dixon Ganassi/Chevy 223.119 40.3373s +0.3418s 125 9. Kurt Busch Andretti/Honda 222.770 40.4004s +0.4049s 95 10. EJ Viso Andretti/Honda 222.695 40.4140s +0.4185s 90 11. Tony Kanaan Ganassi/Chevy 222.635 40.4249s +0.4294s 131 12. Ryan Briscoe Ganassi/Chevy 222.132 40.5165s +0.5210s 39 13. Josef Newgarden Fisher/Honda 222.082 40.5255s +0.5300s 105 14. Simon Pagenaud Schmidt/Honda 221.862 40.5658s +0.5703s 96 15. Will Power Penske/Chevy 221.735 40.5890s +0.5935s 67 16. Oriol Servia Rahal/Honda 221.529 40.6267s +0.6312s 53 17. Alex Tagliani Fisher/Honda 221.408 40.6489s +0.6534s 43 18. JR Hildebrand Carpenter/Chevy 221.266 40.6750s +0.6795s 79 19. Jack Hawksworth Herta/Honda 221.257 40.6767s +0.6812s 61 20. Graham Rahal Rahal/Honda 221.107 40.7042s +0.7087s 93 21. Jacques Villeneuve Schmidt/Honda 221.101 40.7053s +0.7098s 70 22. Takuma Sato Foyt/Honda 220.891 40.7441s +0.7486s 66 23. Sage Karam Ganassi/Chevy 220.543 40.8083s +0.8128s 64 24. Townsend Bell KV/Chevy 220.307 40.8520s +0.8565s 88 25. Pippa Mann Coyne/Honda 220.206 40.8708s +0.8753s 44 26. Sebastien Bourdais KV/Chevy 220.116 40.8876s +0.8921s 87 27. Ed Carpenter Carpenter/Chevy 219.647 40.9748s +0.9793s 34 28. Carlos Huertas Coyne/Honda 219.246 41.0498s +1.0543s 54 29. Martin Plowman Foyt/Honda 218.852 41.1236s +1.1281s 48 30. Charlie Kimball Ganassi/Chevy 218.229 41.2410s +1.2455s 17 All drivers use Dallara chassis