What we learned at the Nashville round

Every event produces data. The Nashville round last month gave us three specific setup findings worth writing down — both because they apply broadly and because the track's characteristics made them more obvious than they would have been somewhere else.

The track context

The infield configuration is heavily asymmetric. Tight, slow left-handers into fast, sweeping rights means the car loads and unloads differently than a more balanced circuit. That asymmetry was useful — it showed problems in the chassis that a more symmetric track would have hidden for another event.

Finding one: rear tire temperature differential

The car came off session two with a left rear that was 20 degrees cooler than the right at the same tread depth. Alignment was within spec. Corner weights were close but not equal.

The adjustment was a ride height correction on the rear-right corner — two turns on the collar — which brought the cross-weight from 51.4% to 49.8%. Session three, the temperatures were within four degrees of each other, and the car stopped pushing at exit on the left-handers.

The lesson: tire temps are telling you where the weight is. If your numbers look right on paper but the temps don't match, trust the tires.

Finding two: brake bias was further forward than it needed to be

The car pulled slightly left under heavy braking in session one. Not dramatically — just enough to require correction. We moved the bias bar forward one click and the pull got worse. Moved it back two clicks from baseline and it straightened out.

This was a reminder that brake pull is not always about the brakes. Sometimes it's about the bias relative to the heat those brakes are actually generating in that session. The fronts were warmer than expected because the tight left-handers were loading them asymmetrically. Moving rearward brought the balance to where the temperatures actually were.

Finding three: damper clicks that worked in practice did not work in competition

The car was set up for practice pace. When competition sessions pushed the pace up, the rear became unsettled through the fast sweepers. We added two clicks of rebound on the rear and the instability went away in the next session.

The underlying reason: at higher cornering speeds, the rear was rebounding too quickly after the crest before the sweeper. Slowing the rebound gave it time to settle before the load came back. This is the kind of thing that is hard to diagnose without knowing what changed between practice and competition. The data log made it readable.

What this means for setup work generally

None of these findings were surprising in isolation. They were useful because the combination told a story: the car was overloading the right side, forward-biased under braking, and too fast in rear rebound at speed. Three separate symptoms pointing at a setup that was slightly off center, consistently.

A single session without data would have produced a feeling, not an answer. Three sessions with temperature readings, bias observations, and damper notes produced three specific changes and a car that was faster in the last session than the first.

We document this because it makes the next event faster to set up. The setup sheet goes with the car. The data from this event is the baseline for the next one.