Playing the angles
Without traction control, more downforce on IndyCar Series cars could be one way to approach the twists and turns of the 1.8-mile temporary street circuit for the Honda Grand Prix of St. Petersburg. Then again, drivers might choose straight-line speed in lieu of cornering.
"Personal preference," said A.J. Foyt Racing's Darren Manning, driver of the No. 14 ABC Supply Co. Dallara/Honda/Firestone. Either way, the sanctioning Indy Racing League has built in front-wing adjustments on the five road/street courses this season. While the end fences must remain parallel to the surface, slots were cut into them to allow 0-5 degrees positive or negative movement.
"Without increasing the cost, we've been able to give the teams a wider platform to adjust the car," said Les Mactaggart, senior technical director for the sanctioning body. "There will be some drivers who will be able to drive the car faster because they can have a bigger window to change the aerodynamics of the car. It doesn't seem like a lot, but you put 5 degrees in the front wing and it increases the amount of front-wing downforce.
"Sometimes it's more efficient to put the angle in the front mainplane not in the back end because you get more drag. The more you stand something up, the more drag it creates. But if you have a larger item you can put a smaller angle in it and get the same amount of downforce with less angle, you get less drag. Then you get a quicker car. It gives the teams a bigger window to explore many more settings."
The changes won't be able to be made during pit stops.
"You'd set the mainplane angle during a practice session, and adjust the flaps (atop the mainplane) during the race," Mactaggart said. "It's something they'll change during practice. Flaps are completely free to change.
"Everybody has the basic information. It's up to the teams to optimize that information for that particular driver." Manning said drivers would have a tendency to experiment on longer road courses, such as Watkins Glen International, than on the scenic streets of St. Petersburg.
"It only really affects road courses where you have hugely long straights and a tight infield," he said. "There are cars out there that will run no downforce, so they might run negative 5 degrees. There are other cars that will run a bit more downforce, so they are a bit slower on the straights so they might run flat on the front wing. Most of the racetracks we will be going to will be full downforce and no trimming out to get straight-line speed. You'll be wanting as much grip as possible." IRL PR