The 33-year-old Spaniard raced for the team in 2006 and, after a 2007 which saw him drive for a back-up for Forsythe, finished the season with them in Surfers Paradise and Mexico City.
And he thinks continuity will be a big help for him.
"I am very excited to have the opportunity to continue with PKV Racing," said Servia. "I know the team and they know me. This will be only the second time in my whole career that I am able to race with a team that I have been with before.
Conquest to run two cars this year
"I feel that the relationship the team and I have established in the past will be very important as we compete for the championship in 2008."
Servia has one ChampCar win to his name - which came in Montreal in 2005. He finished second for Newman/Haas Racing in what remains his best season to date.
And team co-owner Jimmy Vasser, the 1996 champion, added: "We believe that having Oriol compete for the team provides us with the best opportunity to continue developing a championship-calibre programme.
"Oriol, who is not only one of the most experienced and best drivers in the series, but also a good friend, gives us the best chance to contend for the championship."
The team plan to race two cars in 2008 and are set to decide who will be Servia's team-mate after the Sebring tests later this month.
Power and Servia in IRL move
Forsythe to close doors