A race team starts its preparation for the next track by reviewing all the data collected during previous visits. But what if there’s no data to review?
That’s the situation teams faced this week as they visit the repaved and reconfigured Atlanta Motor Speedway.
It’s Always a New Track
For engineers like GM Racing’s Nick Fishbein, the last few years of schedule shakeups and rules modifications have made change a constant in NASCAR.
“I don’t know that preparing for Atlanta is that much different than just preparing for a track, period, especially in the Next Gen environment where everything is new,” Fishbein said.
Even the relationship between manufacturers and teams is changing.
“Not so much because of the Next Gen car,” Fishbein explained, “but a general evolution toward more ingrained support.”
Centralization lets manufacturers reduce duplication of effort and gather more data.
But how do you gather data for a track before it’s even been built?
Jumping the Start
Developing a computer model for a race car running a specific track is an iterative process. You start with what you have and what you can make educated guesses about. From there, every new piece of data helps you refine the model.
Engineers started thinking about Atlanta the moment the ink dried on the blueprints. Fishbein’s group based their model for Atlanta on data from similar tracks, like Daytona and Charlotte. Both tracks hosted early Next Gen testing sessions and actual race data could be added to the model after the Daytona 500.
Experiments on seven-post rigs, engine dynos, and tire-test machines let teams start working on their models even before the track is finished.
Testing Tires Indoors
One GM Racing group focuses on tires, using tire-test machines to press a tire against a rotating piece of sandpaper that mimics a track surface. The picture to the right is a FlatTrac tester at Goodyear. GM Racing uses a similar machine at SoVa Motion.
Although lab data can’t replace race data, it does allow engineers to control variables impossible to control at a track. They can modify everything from force on the tire to its slip angle and camber. If you know a lot about tires in general, it’s not so hard to develop a realistic model for a track that doesn’t yet exist.
Of course, it’s one thing to know the conditions that maximize tire grip. It’s another to get your car set up to provide them.
The On-Track Tire Test
Atlanta’s schedule called for the track to be completed in time for a tire test in late 2021. A pipe burst on the backstretch over Thanksgiving, ruining the subgrade — the all-important foundation for the track. That pushed the tire test back to January 2022.
The months-long delay didn’t worry Greg Stucker, Goodyear’s director of race tire sales.
“We have such a long history with NASCAR and track changes,” he said, “and a good idea of the tire design based on the whole Next Gen package.”
The tread compound, however, needed a physical test. Wear on a tire helps dissipates heat, but a brand-new, smooth track doesn’t offer much wear. Without enough heat dissipation, tires can blister.
“That’s the one area,” Stucker said, “that needs on-track testing.”
The tire test did more than just finalize the tread compound.
“I asked the drivers for feedback,” Steve Swift, senior vice president of operations and development at Speedway Motorsports said. “All three said the dogleg coming off turn four was awkward.”
Drivers were worried that the wall angle relative to the racing path would lead to harder, more head-on collisions rather than glancing blows.
Swift drove it himself. “Even as an engineer, I could tell it was an issue.”
They moved the outside wall in by about 5 feet at the dogleg, which required constructing 320 feet of wall, SAFER barrier and…
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