BustaWrench › Answers › What tyre pressures should I run in iRacing?
The short answer
Start lower than you think — usually 2–4 psi below whatever real-world hot pressure you have read — and let the tyre build its own number. Pressure climbs 2–3 psi from cold to hot in iRacing and the core lags the surface, so copying a track-day figure leaves you over-inflated and vague. Then read temperatures after a five-lap run and move one psi at a time.
Pull a psi number off a track-day forum, dial it into the sim, and you will be over-inflated by the time the tyre reaches operating temperature. The car feels numb, slidey and slow to respond.
The sim's heat model is its own thing. Real-world setups account for chassis flex, a particular surface and a particular ambient — and real-world drivers get tyre warmers or an out-lap. In the sim you launch cold every session.
In iRacing the tyres build heat fast, especially over the first two laps, and cold pressure can climb 2–3 psi. The core temperature lags the surface, so the number you set cold is not the number you race on.
Start 2–4 psi below what a real-world hot figure suggests and let the tyre build its own pressure from there.
After a five-lap run, read the temperatures rather than only the pressure. Middle of the tread 10°C hotter than the edges: drop a psi. Edges hotter than the middle: add one.
One psi at a time, then re-read. No spreadsheet required.
Ideal pressure is car- and track-specific. If you are unsure how the current tyre model builds heat, ask a coach — that beats a season of guessing.
The free first-30-days guide covers car control, setup basics, racecraft and a practice routine that fits around a real life. No email course, no upsell funnel — read it now.
Read the free guide →