Iowa IndyCar: Simon Pagenaud gives Penske its 500th pole

Third-runner Tony Kanaan set the early pace to continue his strong form from practice in his Chip Ganassi Dallara-Chevrolet, but a quartet of Penske cars midway through the session put first Helio Castroneves and then Pagenaud top.

Pagenaud pumped in a 185.855mph two-lap average - 0.4mph quicker than Castroneves.

From there it was the Chevy trio of Charlie Kimball, Max Chilton and Josef Newgarden that looked to challenge with frontrunning pace, but they finished fifth, fourth and second respectively.

Newgarden's performance was just 0.04s off Pagenaud's pole time as he earned the outside front row spot.

A bumpy inside line made worse by last month's NASCAR Xfinity race upset the standard low qualifying line through Turns 3 and 4, causing some of the field to compromise on the racing line.

Andretti's Ryan Hunter-Reay and Marco Andretti - both of whom spun in practice earlier - took their Dallara-Hondas onto the less bumpy high line, while the likes of Takuma Sato and Castroneves braved the bumps on the low line through the second part of the lap.

The Hondas were visibly struggling throughout the session, with many drivers complaining of understeer.

Mikhail Aleshin was the only Honda-powered car to make it into the top 10 following his strong lap as the 17th driver on the rubbered-in track.

QUALIFYING RESULTS