Shown here at Sebring, the returning Vipers to will hit the Le Mans circuit for the first time on Sunday.

Sunday, June 9’s sole Le Mans test day prior to race week is a busy and tense time for teams and drivers alike.

Teams and drivers who have not previously raced at Le Mans are especially anxious for track time.

Each team lays out a program for a series of runs on the 8.5 mile circuit to evaluate set-ups, tires, aerodynamics, gearing, fuel economy and driver performance and comfort.

With top lap times ranging from the high 3:20s for the top prototypes to nearly a full minute longer for the GTE-AM cars, teams want to learn something every run to prepare for race week and the June 22-23 race.

The first of Sunday’s four-hour sessions runs from 9:00 am to 1:00 pm local time. After a brief one-hour lunch break, the second session rolls from 2:00pm to 6:00Pm local time. Any major mechanical issues or crashes can prove costly in terms of track time.

A few teams will take advantage of opportunities to run an extra car. Audi has provided a fourth R18 e-tron Quattro to assist Michelin in developing new, narrower tires, in preparation for the new 2014 regulations.

Scott Tucker’s Level 5 team will also have a second car in play Sunday to provide additional data and track time.

The latest weather forecast is for a high temperature of 75 degrees, with a 40 percent chance of rain.

There is no night running until Wednesday evening of race week.