Logging real dyno sessions and lap times, or self-reporting BHP and torque if you haven't been on a dyno yet, and what shows on your public vehicle profile either way.
Garage > your vehicle > Performance > Dyno Results > Add Dyno Session records the date, the tuner and dyno centre if you know them, BHP at the wheel, boost, torque in both lb-ft and Nm, what fuel was used, and an optional graph image from the run. Your most recent session becomes the "current peak power" figure shown at the top of the Performance tab.
The Lap Times tab works the same way: pick a circuit from the list or enter a custom one, the date, your lap time, conditions (dry, wet, or damp), and tyre compound if you want to note it. Your quickest logged time at each circuit gets a PB badge automatically.
If you haven't had a real dyno session yet, the Edit Vehicle page has an optional Performance section for your own estimated or manufacturer figures: BHP with a wheel or crank dropdown, and torque with a Nm or lb-ft dropdown. These only ever show as a fallback, the moment you log a real dyno session, that takes priority everywhere.
The Performance tab on your public vehicle profile always shows a current peak power card: a real dyno figure if one exists, your self-reported figure labelled "owner-reported, not dyno-verified" if that's all you've entered, or "not recorded yet" if neither. Full dyno and lap time history is visible to you and to Pro members; everyone else sees only the single latest entry, with a prompt to unlock the rest.