Continuing his series of aero tuning options at the 1.5-mile Texas Motor Speedway oval and the most recent road course race at Road America, Dale Coyne Racing engineer Craig Hampson (pictured at left, above, with Sebastien Bourdais) takes RACER inside the aero tools available at the 0.875-mile oval for this weekend’s Iowa Corn 300.
“From when Oriol Servia and Juan Montoya tested here last year with the new bodywork, IndyCar tried a high-downforce package with the full road course aero setup, and a lower-downforce setup, and asked the drivers which one they preferred,” he said. “The decision among the drivers and engineers was the low-downforce package would make for better short-oval racing. And not only for Iowa, but also Phoenix and Gateway; all three are run to the same rules.
“It’s effectively a road course aero package, but we’re required to remove the top element from the rear wing, so it’s two elements — the main and the upper flap — instead of three, and to balance the car aerodynamically, we are also required to remove the upper elements from the front wings, giving us two elements instead of three as well.”
Beneath the cars, a road course specification is also required with one key change.
“We can use a spec 3/8th-inch wicker on the rear wing on the upper element, and on the front, we can add front wing extensions, which you’d only use if you were trying to run a very high level of aero balance,” Hampson continued.
“We use the road course underwing configuration with the holes at the front of the sidepods filled in. At the back, we use the tall strakes and sidewalls fitted. Different than the road course, we install the ‘blisters’ to the outer edges of the floor that mimic the stabilizing effects of the ‘dome skid’ we used last year.”
With the former Chevy and Honda aero kits in use from 2015-2017 at Iowa, teams had amble downforce to utilize. In the switch to the lower-downforce universal aero kit, an average number of 5400 pounds of downforce used in last year’s race has been cut by approximately 1000 pounds to a maximum of 4400. With less aero loading to offer their drivers, Hampson expects race engineers to follow the same direction on downforce application.
“Last year, with the manufacturer aero kits, we would have gone for maximum downforce in the race but trimmed out quite considerably for qualifying,” he said. “With the reduction in downforce this year, it’s my expectation we’ll use all of the downforce available in the rules at all times — even in qualifying.
“You could, if you wanted to try and trim, to remove the rear wicker, or go down one hole on the rear wing, but I don’t think it’s something many people will do. And keep in mind that 13 drivers recently tested at Iowa, and we weren’t one of them, so we’ll have 45 minutes to try a few things before qualifying. But almost half the field will be pressed for time to work through aero options because they chose to use their limited number of test days at different tracks than Iowa.
“We only have two in-season test days, and they must be used wisely. We didn’t choose Iowa, but we’ll go to Gateway. So we will be among the teams with a lot of work to do in an efficient manner, and that may preclude trying much other than high-downforce running.”