The 35-year-old Canadian has been left jobless after Rocketsports decided against renewing his contract at the end of last season - preferring instead to test the likes of Xandi Negrao, who can bring much-needed finances to the team.
And PKV general manager Mark Johnson thinks Tagliani will be desperate to prove his worth to the team.
"Alex is a very competitive and capable driver that has consistently placed among the leaders in races and the championship standings over the years," said Johnson.
Servia joins PKV
"Testing Alex in Sebring will give PKV Racing an opportunity to receive the benefit of his experience as we work through the various projects we have for this test. In addition, it will give us a chance to see how Alex meshes with our team as we proceed with our search for a second driver."
Tagliani made his ChampCar debut in 2000 and almost won on his debut at Homestead with Forsythe Racing, before he incurred a drive-through penalty for passing the safety car while entering the pit-lane.
The first, and so far only win, came four years later with Rocketsports at Road America in what proved to be his best season as well, with the driver coming seventh in the championship.
In all, he has started 131 races, five of them from pole position, but he is not ready to hang up his helmet just yet.
"I am very excited and grateful for the opportunity to test with PKV Racing. It's a first-class organization," said Tagliani.
"This is a team that is capable of winning the championship this year and it would be a dream come true for me to be with PKV in 2008.
"I think I can help them get to the top of the standings, but first things first and that is to do get our work done and have a good test in Sebring. After that we will see where things go from there."
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