NASCAR is expanding practice adjustments for NASCAR O’Reilly Auto Parts Series teams at Darlington Raceway this weekend by adding rear springs to the list of allowed changes during practice.
NASCAR teams have a limited list of adjustments that are allowed during practice sessions and since practice was condensed during the Covid-19 pandemic, that list has prevented most parts from being swapped and limited adjustments on others.
The typical adjustments that have been allowed over the last few years are similar to those that might be completed during a pit stop, such as adjusting tire pressures or adjusting a trackbar/shock using the adjuster wrench through the window.
Removing or replacing parts has mostly been outlawed over the past few years, especially at the rear of the car. Practice sessions in the NASCAR O’Reilly Series were expanded to 50 minutes at the start of the year but the limited adjustment rules remained, which limited how much teams could actually benefit from the second set of tires if they chose to use them. The NASCAR Cup Series followed with a similar extension, starting at New Hampshire Motor Speedway a few weeks ago, but their allowed adjustments list did not expand outside of an additional tire set.
NASCAR has allowed the rear springs to be changed in the NASCAR O’Reilly Series a couple of times this year, but it was mostly due to special circumstances like the use of resin and the tire dragon at Dover. The fact that it’s being allowed at Darlington Raceway along with the extra set of tires appears to signal that they’re willing to be more flexible with practice, which is a positive change.
The change was welcomed when checking in with a variety of personnel in the garage ranging from competition personnel to team leadership, as most saw it as an opportunity to use parts they already own to help them make their cars better. Teams that don’t have significant simulation resources see it as something that they can grasp as well, allowing them to get closer to the front end of the field.
Allowing rear spring changes will now allow teams to have a wider window of adjustment outside of just adding or removing springs rubbers to tweak rate in small increments. This will give teams more opportunities to tweak a setup and not be solely reliant on hitting the correct spring combination during simulator prep ahead of a race weekend. Well-resourced teams at the top end of the grid will always see benefits from any added adjustments but this change will also help some of the smaller teams on the grid without huge additional cost. This will be significant at a track like Darlington where a right rear spring change can significantly impact how a car turns and teams won’t be stuck with what they installed at the shop.
Should teams be allowed to change brake pads? 👀@BoziTatarevic breaks down how NASCAR and IMSA differ when it comes to parts changes and how to get a competitive edge.
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On a recent episode of NASCAR Inside The Race, I discussed how practice could be improved to make teams more competitive and one of the examples we used was spring changes and how much of an impact they have during IMSA practice where they are allowed.
Crew chief Todd Gordon suggested that NASCAR could allow Cup Series teams to bring multiple sets of shocks to be inspected and sealed during a race weekend so that they could have more spring options and just be reliant on incremental changes to the single set of springs that they pick.
The allowance of rear springs change for NASCAR O’Reilly Series teams this weekend is a step in that direction and the learnings from that could pave a path for additional adjustments and parts changes to be allowed in Cup or Truck Series in the future.
