INDIANAPOLIS (AP) -- IndyCar will reduce downforce in the cars for the race at Iowa Speedway on Saturday night.

The decision was announced Monday and will reduce downforce by about 9 percent.

IndyCar vice president of technology Will Phillips says reducing the downforce makes the cars difficult to drive, and most of the drivers have been asking for that challenge. The drivers unanimously voted for less downforce two weeks ago at Texas to eliminate the pack racing that develops on high-banked ovals.

Aside from the reduction of downforce and removal of the rear wicker, IndyCar will use the same short oval aerodynamic package it used last weekend at Milwaukee.

IndyCar also said it will set the fields for Friday night's qualifying heat races by lap times recorded in the second practice session.

SI Apps
We've Got Apps Too
Get expert analysis, unrivaled access, and the award-winning storytelling only SI can provide - from Peter King, Tom Verducci, Lee Jenkins, Seth Davis, and more - delivered straight to you, along with up-to-the-minute news and live scores.