Ryan Briscoe was immediately in charge and setting the pace on Friday morning at Auto Club Speedway in Fontana, California as he returned to the #5 Schmidt Peterson Motorsport car, substituting for the injured James Hinchcliffe.
Briscoe set the fastest lap of the session, clocking in at 217.451mph (33.1109s) on the 2-mile, D-shaped oval putting him two hundredths of a second faster than Andretti Autosport's Marco Andretti, marking a rare 1-2 success at the top of the timesheets so far this season for Honda.
CLICK: Full practice 1 times from Auto Club Speedway
“With these aero kits, everyone is running different levels of downforce, which mixes it up a little bit more,” explained Briscoe, who added that he was happy with the car so far but adding that it was just the start of a long weekend.
“It's such a long race and so many lanes to choose from I think the goal has to be having a good race car," he said. "Hopefully we're decent in qualifying, but it's not the end of the world if we're not."
Although it's not yet been confirmed by the team, it's expected that Briscoe will now stay in the #5 car for most of the remaining races of the 2015 season and certainly those on oval circuits. Until now prior commitments in other championships - most notably the 24 Hours at Le Mans - have meant that the 33-year-old Australian has been sharing outings in the car with young American talent Conor Daly. Hinchcliffe is considered highly unlikely to return to racing this season as he needs further surgery to enable to him to complete his recovery following a major practice accident at Indianapolis in May.
Sweltering track conditions in excess of 100F meant that Briscoe and the rest of the drivers were all some way off last year's two-lap pole-winning effort by Helio Castroneves which was 218.540mph, while the previous year his fellow Penske driver Will Power recorded a two-lap average speed of 220.775mph for pole.
The highest-placed Chevrolet car was that of Simon Pagenaud in the Penske #22. He was followed by a brace of Ganassi car with Charlie Kimball just edging out his more experienced team mate Tony Kanaan for fourth place. Kanaan won this event last year when it was the 2014 season finale at the end of August.
Fresh from victory two weeks ago in Toronto, Josef Newgarden showed that CFH Racing had overcome its problem with oval set-ups experienced in an uncharacteristically dismal showing at Texas Motor Speedway earlier in June by finishing practice as the sixth fastest runner ahead of Carlos Munoz (Andretti), Scott Dixon (Ganassi), Juan Pablo Montoya (Penske) and Takuma Sato (AJ Foyt Racing).
Last year's pole winner Castroneves ended up being pushed just outside the top ten in 11th place ahead of Bryan Herta Autosport's Gabby Chaves and fellow rookie Sage Karam in the #8 Ganassi car. Reigning Verizon IndyCar Series champion Will Power could only manage 14th place in the first session putting him just ahead of Briscoe's SPM team mate James Jakes.
The top 15 were all within half a second of Briscoe's time, and all but one of the 23 cars taking part were well within a second of the leader. The exception to the rule was Pippa Mann who returns to the race seat of the #18 Dale Coyne Racing Car putting her alongside Tristan Vautier who retains the #19 car this week and who finished practice as 17th fastest overall.
The first session had been scheduled to last for one hour and 45 minutes in total, with the first 60 minutes reserved for rookie drivers to get used to the high speed oval before they were joined for the remaining 45 minutes by the more experienced drivers in the field. The incident-free session ended up being slightly extended by five minutes to make up for time lost during two track inspections and general clean-ups.
All the drivers have a second 75 minute practice session available to them on Friday afternoon at 12.45pm-2pm local time (8.45pm-10pm BST) before heading into qualifying later in the day at 4.45pm-6pm (12.45am-2am BST).
Qualifying will consist of single car time trials as is routine for IndyCar events held on ovals, rather than the three-round elimination group qualifying utilised at street and road course events.
There will be no pre-race warm-up session on Saturday, just a one-lap systems check in the morning. The race itself will get underway just after 1.30pm local time (9.30pm BST).
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