Brake, damper changes on IndyCar’s radar after recent IMS test

The IndyCar Series used its recent test on the Indianapolis Motor Speedway’s 2.5-mile oval to gather feedback and data on two technical changes being considered for its current and future car.

Evaluated by Ed Carpenter Racing’s Alexander Rossi, the 2016 Indy 500 winner, in the No. 20 Chevy, and Rahal Letterman Lanigan Racing’s Takuma Sato, winner of the 2017 and 2020 Indy 500s, in the No. 75 Honda, a different spec brake package from the U.S.-based Performance Friction Corporation (PFC) was tried along with two unique spec dampers supplied by the Swedish company Ohlins.

IndyCar’s brake specification has made use of a one-size-fits-all approach with calipers, discs, and pads that are used on road courses, street courses, and three different types of ovals. But that’s expected to change with a custom oval caliper for 2026 that’s smaller, lighter, and provides improved response.

As fans have witnessed in recent Indy 500s, some drivers have struggled to slow or control their cars coming off of Turn 4 as they decelerate from over 200mph to 60mph on entry to pit lane. Evaluating a downsized brake caliper which grips faster – after drivers spend extended periods running around big ovals without using the brakes – was raised with PFC. The package run by the two teams produced favorable reactions, as drivers reported having solid brake pedals and immediate responses upon entering pit lane.

“We have a brake package right now, from a caliper standpoint, that is consistent throughout the season. What we’ve started to look at is, there’s an opportunity to really enhance that package when it comes to ovals,” Mark Sibla, IndyCar’s Sr. VP of competition and operations, told RACER. 

“There’s an opportunity to a get a little bit of weight out, but also impact some things that just will make the performance of those a little bit better as far as what we’re looking for.

“PFC was in attendance and they brought a couple of new units that we hadn’t yet tested. The teams went out with their current packages – just as you would with any test; start with what you know – and then they would start to move to variations on this new caliper package, and we got what was just really, really good feedback from both of the drivers. It seemed very, very positive, the direction of what PFC had brought and how it was performing.”

IndyCar has made use of six-piston calipers at the front and the back of the Dallara DW12 since its debut, and with where the 2026 oval package is headed, a reduction to four pistons at the rear is anticipated.

A switch to a series-controlled damper solution is also highly likely, but on a longer runway. IndyCar’s new-for-2028 chassis is the changeover point being considered.

The IMS test, which featured Takuma Sato (above) along with Alexander Rossi, could be a step towards a eventual move to control dampers. Chris Owens/Penske Entertainment

Since 2012, dampers have been the one truly open area of suspension development to tailor the DW12’s handling to a driver’s needs. As a result, intensive research and development takes place throughout the year to find improvements, and as the lone exemption among an array of spec suspension components that cannot be modified, budgets for damper R&D and the six-figure salaries for damper experts to lead the quests for gains has skyrocketed over the last 14 seasons.

Stemming from a volley of complaints from team owners who want to slash their annual damper budgets, the series took its first steps towards a spec-like solution for Rossi and Sato to sample.

“There were two options of spec dampers that were being looked at, and this was testing for 2028,” Sibla said. “They began with what they use now, and then they moved to a larger size damper, and then then a smaller size damper. And I think it was important for us to do, and it will lead to more testing because it clearly is a very expensive area.

“It’s also an area of differentiation that teams are using to compete against each other. The first thing was, is this an area where you move into a spec product, and instantly, you not only save money, but how drastic is the change in feel? And there was some really good feedback from both drivers.

“What it led to is one of these spec options is just not an option. And then with this other unit, there’s some more things we want to look at to see if there are ways to make it feel a bit more consistent with what they experience now. So it was just an immensely helpful first step because it’s a huge topic. It’s something that’s been out there for a long time, but we needed to start to get some answers and some driver feedback and team feedback.”

The next step in the process is to review their input against the data generated by the DW12’s onboard computer system and present the findings to IndyCar’s team owners.

“There’s a lot of data,” Sibla continued. “We’re going to go through and say, ‘Okay, now we need to take a look at this next evolution, see how that feels, see what that experience is like.’ And then from there, we’ve got to reconvene internally and also reconvene with our stakeholders and share what we’ve learned, here’s what we know. Here are all the different elements, financial differentiation. What is the direction that we want to head on this ‘28 car? We just need more data around it so that we’re making the right decisions for the future.”

The revised oval brake calipers appear to be in the works for next year, and could carry over for use with the next chassis.

“We’re looking at this as an implementation for the ‘26 season, and I think it could be used up to all ovals,” Sibla said, noting their primary use would be for the Indy 500. “Still some work to be done there, but it certainly could be a short-term and long-term solution.”