The former IZOD IndyCar Series driver, who will return to the Firestone Indy Lights with AFS Racing/Andretti Autosport, posted the quickest time of both days with a 1:16:7046.
The 21-year-old Colombian, who spent time in the IZOD IndyCar Series in 2010 and 2011, said he is getting more and more comfortable with the team, which he last drove for as a rookie in 2009.
"It's great to be back with Andretti Autosport," Saavedra said. "I remember we had a great test here in 2009, and I wasn't to race with them here, but right now we have a very competitive car."
Another returning driver, Victor Carbone of Sam Schmidt Motorsports, was second fastest overall with a time of 01:17.0544 that he posted in Practice 5 on Tuesday morning. Gustavo Yacaman of Team Moore Racing, who was fastest at the Sebring Open Test, was third fastest. Sam Schmidt Motorsports teammates Esteban Guerrieri and Tristan Vautier rounded out the top five.
Firestone Indy Lights ran a combined total of 1205 laps during the two-day event in its first official series test of the season. The 2.3-mile road course plays host to the second race on the series' 2012 calendar, which will run on April 1.