All 25 IZOD IndyCar® Series drivers, including first-time competitor Lucas Luhr and Sausalito native J.R. Hildebrand, are expected to participate in an INDYCAR-sanctioned test at Sonoma Raceway on Wednesday, Aug. 21, just two days before the GoPro Grand Prix of Sonoma, Aug. 23-25.

The 9 a.m.-5 p.m. session on the 2.38-mile, 12-turn road course is open to ticket-holders for the GoPro Grand Prix of Sonoma and spectators who purchase a race ticket at the gate.

Fans can watch the test session from open seating areas and attend the lunchtime press conference with select drivers in the Wine Country Winner's Circle. The Raceway Café will also be open for lunch.

It will mark the first test of the year in Sonoma for INDYCAR points leader Helio Castroneves and his Team Penske teammate Will Power, as well as Target Chip Ganassi Racing teammates Scott Dixon and Dario Franchitti.  All four drivers have posted wins at Sonoma Raceway and will look to return to the Wine Country Winner's Circle.

It will also be the first full-day test for five-time American Le Mans Series champion Luhr, who is confirmed to make his INDYCAR debut with Sarah Fisher Hartman Racing in Sonoma.  Hildebrand, a Bay Area native, will also return behind the wheel of the No. 98 Barracuda entry for Bryan Herta Autosport.

Tickets are still available for the GoPro Grand Prix of Sonoma, including the Brasil IT+ Total Access Package, which includes a race-day Q&A session with Graham and Bobby Rahal, a reserved ticket to the GoPro Grand Prix of Sonoma on Sunday, Aug. 25, and a garage/pit/pre-race pass all for $99.  Kids 12-and-under are admitted FREE to the GoPro Grand Prix of Sonoma and parking is FREE. For more information, visit racesonoma.com/indycar or call 800-870-RACE (7223).