General Motors is wrapping up a new driver‑in‑the‑loop simulation of the San Diego street course before the race weekend.
Building a virtual baseline
GM’s simulation team, led by Keith Rodden, receives a base map of the finished track from rFactor months in advance.
rFactor scans every surface, wall, and roadside marker, creating a first‑pass digital terrain that GM refines with imagery and on‑site checks.
Engineers overlay Chevrolet’s next‑generation cup car models onto the map to set preliminary handling parameters.
Grip data and on‑site validation
Goodyear supplies detailed grip metrics for each asphalt patch, which GM incorpates into the simulator’s physics engine.
In a creative quality‑control step, drivers walk the course and drag their shoes across the surface to confirm the grip values match physical feel.
From photos taken in the media walk, the team verifies that the digital surface textures align with the real‑world finish.
Testing, feedback and final tweaks
GM’s own driving engineers ride the simulator to spot inconsistencies, aiming for an estimated lap time within ±3 seconds of the target.
After initial validation, product‑development drivers like Connor Zilisch refine the model further in on‑site runs, feeding corrections back to the software.
Updates continue daily; a week before the race, Rodden announced a significant release to sharpen the driver‑experience simulation.
Post‑race refinements
Immediately after the event, two drivers conduct a post‑race simulation session while the track’s characteristics remain fresh.
This session validates every element of the tool and the data, driving iterative improvement for future iterations.
Returning to Chicagoland – a different challenge
The Chicago circuit, though familiar, has aged, prompting a full re‑scan with rFactor and new tire testing in April.
Wheelforce transducer measurements capture longitudinal and lateral forces, as well as torque, enabling precise updates to shock limiter settings.
Test results showed the surface has become rougher; Rodden predicts these bumps will further test the Cup cars’ suspension limits.
What it means for the upcoming Cup race
Rodden sees a chance for sustained racing action when the Cup series returns to Chicagoland next month, hoping the groove spreads and a thrilling duel unfolds.
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