Gordon Kirby
Aero kits increase Indy’s traction
IndyCar hopes to add some variety to its Dallara DW12 spec car formula next year by allowing its two competing engine manufacturers, Honda and Chevrolet, to design their own distinctive aero kits. IndyCar will allow Honda and Chevrolet to do six days of aero kit testing between October and January, and the teams will have to place their orders by November 1 to receive them by March 1. IndyCar has pegged the cost of a kit at $75,000 and the first event with the aero kits will be the St Petersburg street race in March, following a pair of season-opening fixtures in Dubai and São Paulo.
In August I discussed the state of Honda’s aero kit development with Honda Performance Development’s COO Steve Eriksen.“Our aero kits are proceeding to the schedule that IndyCar has laid out,” Eriksen said. “There’s quite a bit of work involved in them. I think when you see what the aero kits look like, you’re going to be surprised how open the rules are.
“IndyCar has defined some boxes, and you have to work within those. But apart from that it’s pretty open. I think the target of having distinction between a Chevy car and a Honda car is going to be achieved because it’s so open on the rules that you’re going to see quite a bit of variation between the cars. “I think people will be looking at all the little details on the car, and it’s going to generate quite a bit of interest.”
Eriksen said most of Honda’s aero kit design work has been done with CFD. “Just as we did in IndyCar aero development years ago, and just as we do on the sports car side today, the bulk of the development is done digitally,” he said.
“Then we had wind tunnel tests to verify the correlation between the virtual world and the real world.
“That so far has shown very good correlation, so we believe that the projected performance targets that we’re seeing are going to be met in the real world.
“Development in the digital world is wonderful because you don’t have to throw away any parts, and at this point it looks like we’ve got every likelihood of reaching the target we set. It’s going to be a pretty impressive performance.”
Eriksen is convinced Honda’s aero kit will be substantially better than the existing Dallara bodywork package and he expects all of Honda’s IndyCar teams to run it. “The teams have the option to run the Dallara current kit or the manufacturer’s aero kit,” he said. “But I can’t imagine them selecting the Dallara kit. There would be no logic to that.”
Once Honda and Chevrolet introduce their aero kits next year, no changes will be allowed through 2015. But for 2016 each manufacturer will be able to chose three defined areas of bodywork for further development. “There’s a series of boxes surrounding certain sections of the car,” Eriksen said. “You might have a sidepod box, or a front wing, rear wing or engine cover box, etc, and in 2016 you’re allowed to take three of those and revise them further.”
Of course, there’s a conundrum for IndyCar in the arrival of aero kits because many people believe the category needs to reduce downforce and increase power. The existing downforce/power equation keeps the cars close together on the track but makes passing difficult. More downforce without a substantial increase in power would exacerbate that situation rather than making for better racing.
So IndyCar has been testing a modified DW12 with holes in the floor aimed at sapping some downforce from the underwing and balancing the expected gains from the aero kits. Making the new aero programme work in IndyCar’s tightly budgeted world will be a challenge, but everyone hopes it will add fresh interest.