Aerodynamic load. Downforce F = 1/2 rho Cl A v^2 and drag 1/2 rho Cd A v^2, rho = 1.2 kg/m3, A = 1.4 m2. Wing angle moves Cl and Cd together: more angle gives more grip in corners but more drag on straights, so the best setup depends on the circuit.

Tyre grip. Friction coefficient falls with load (load sensitivity): mu(Fz) = mu0 (1 - 0.10 (Fz/4000 - 1)), per tyre, floor 0.6 mu0. Because mu drops as load rises, doubling the load gives less than double the grip.

Friction circle. Longitudinal and lateral demands share one budget: a_x^2 + a_y^2 <= (mu Fz / m)^2. Braking into a corner uses up lateral grip.

Corner speed. Steady cornering on radius R: m v^2 / R = mu Fz, with Fz = m g + 1/2 rho Cl A v^2. For constant mu: v = sqrt(mu g R / (1 - mu rho Cl A R / (2 m))); when the denominator reaches 0 aero grip alone sustains the corner at any speed.

Lap time. Quasi-steady-state: a speed limit from curvature along the 3 m-spaced centre line, then a forward pass (power limit P = 560 kW x 0.97, tyres) and a backward pass (braking), with t = sum of ds / v.

Simplifications, honestly. Point mass (no weight transfer, yaw dynamics, tyre slip angles or temperature/wear), flat-ground physics (the terrain's gentle elevation is cosmetic), constant air density, no slipstream, no gearbox. Numbers are plausible, not a model of any real car. Generic invented car and circuit, not affiliated with any team or series.

Tools. Car and props: Blender 5.2 (named parts, baked AO and livery). Circuit: Unity 6 headless (terrain, spline, scatter, raycast-baked shadow and AO) exported as glTF + JSON. Runtime: Three.js r160 + WebGL.