Helio Castroneves' lap time of 52.1413s was the best that any of the ten drivers involved in the first block of pre-season testing at Sebring International Raceway could achieve during their two days on track - but it was under seven hundredths of a second faster than the times of both of his Penske team mates, Will Power and Ryan Briscoe, on the 1.67-mile, 11-turn circuit.

"Certainly it is great to be on top of the charts, but it doesn't pay anything," pointed out Castroneves at the end of the day. "The first race of the season is what we are looking for. But, it feels great to have a good practice."

Power's performance was particularly impressive. After losing almost all of the morning session while the team cleared up the #12 after his engine bay fire caused by a fuel leak on Monday, he suffered a second minor fire later on Tuesday that forced him to abort what looked to be his fastest run of the day in order to pull into the pits, where his crew were ready to administer highly sophisticated fire suppressants - in the form of buckets of water.

"It wasn't a big issue," Power said about Monday's incident. "Fortunately, we got it out soon enough that we didn't do too much damage that would have lost us the test day today."

As for the test overall, Power was struck by how close the cars were. "It is clear that it is pretty even so far," he said. "Everyone is going to have what they've got. There is no sandbagging or anything. We shall see."

Certainly the Chevrolet-powered runners seemed happy with how things were shaping up. "The more miles we get on these Chevys, the better. I feel like we're ready to go racing in St. Pete," said Briscoe. "The car is feeling strong. Working with the engine guys on the driveability side as well - I think we made a lot of gains there."

Simon Pagenaud and Justin Wilson were the fastest Honda runners at the session, with Pagenaud less than a third of a second off Castroneves best time and feeling positive about the first race of the season.

"It's an exciting moment for IndyCar with three different engines. You can tell the Chevys and Hondas are really close," said the Schmidt-Hamilton Motorsports driver. "It will come down to qualifying [at St. Petersburg] to see who's strongest."

"Not a bad day, it was a reasonable test overall," said a more cautious Wilson, back at Dale Coyne Racing after two years away from the team. "The Honda engine has been really strong and very consistent," he added. "There are a lot of components to this car that are new to us and we are still working hard to see how everything responds to changes, but I think we are getting better every time out."

The cooler, overcast afternoon proved to be better for grip than the morning session and everyone but Andretti Autosport team mates Marco Andretti and James Hinchcliffe improved their time in the final session, with Marco's best time coming on Tuesday morning.

"We're definitely going to be gambling a little bit on setup because we've tried a bunch of different concepts," explained Marco. "So now, it is all about picking the right one to roll off there [at St. Petersburg]. We have to picture the types of corners on this track that replicate over there and hopefully go with the right one. On the Chevy side, it is all good."

Meanwhile Hinchcliffe was the only driver not to improve his time from day 1 of the two-day test. During the Tuesday morning session, Hinchcliffe ran off the track just before lunch and executed a pirouette that sent out clouds of dirt into the air, although no harm was done to car or driver.

"We learned what things don't work, so now we'll work on the other things to pull everything together to find the speed we're missing" said Hinchcliffe, insisting that even a lack of progress was positive at this stage.

HVM finally got some decent running in, after losing most of Monday to an electrical gremlins with the Lotus engine which persisted into Tuesday morning. But eventually Simona de Silvestro was able to run 64 laps and post a time of 53.2312s for the test, just over a second off the lead time set by Castroneves.

"Better day today but still needs lots of improvement!" de Silvestro tweeted at the close of the session. "We will get there!"

Wednesday sees Sebring handed over to the Firestone Indy Lights team for their pre-season test session, before the second block of IndyCar teams arrive for their turn on track on Thursday and Friday.

The cars running at the end of the week include JR Hildebrand (Panther-Chevrolet), EJ Viso, Tony Kanaan and Rubens Barrichello (KV Racing Technology-Cheverolet), Scot Dixon, Dario Franchitti, Graham Rahal and Charlie Kimball (Ganassi-Honda), Mike Conway (AJ Foyt-Honda), Takuma Sato (Rahal Letterman Lanigan-Honda), Ed Carpenter (Ed Carpenter Racing-Chevrolet), Oriol Servia (Lotus Dreyer & Reinbold Racing), Josef Newgarden (Sarah Fisher Hartman Racing-Honda), Alex Tagliani (Bryan Herta Autosport-Honda) and - engine availability permitting - Sebastien Bourdais and Katherine Legge of Lotus Dragon Racing.

Will Power wasn't sure how comparable the times later this week will be with those set on Monday and Tuesday.

"Oh, that is right, I forgot about that - Ganassi will be here Thursday," he said when asked. "It is so hard to tell this track, to be honest. It is a very strange circuit for testing, because I don't think there is any place we go that is like it."

Sebring day 2 testing times available.