How to Plan an iRacing Endurance Race
Endurance racing on iRacing requires meticulous preparation: fuel calculations, driver availability, stint scheduling, and pit strategy. This guide walks you through every step.
Need fuel numbers fast? Open the Fuel Calculator →
1. Choose your race and car class
iRacing offers several official endurance events — the 24h Nürburgring, Daytona 24, Spa 24h, Bathurst 12h, and more — plus community-run multiclass events. Before any calculation, confirm: which car class are you running, what is the fuel tank size, and what fuel consumption per lap to expect. Most teams baseline these numbers from their own practice sessions or community data sheets.
2. Calculate your fuel requirements
Fuel strategy is the foundation of endurance planning. You need to know: (a) fuel per lap (standard and fuel-saving modes), (b) tank capacity, and (c) race duration. From these, compute the number of laps per stint, total fuel for the race, and required pit stops. Use the iRacing Fuel Calculator to do this instantly.
3. Plan your driver stints
With the stint length known (fuel-limited or time-limited), map driver availability against the race schedule. For a 24-hour race with 4 drivers, each driver typically covers 5–7 stints of 50–70 minutes each. Mark blocked windows (sleep, other commitments) before assigning stints. Agree on a cap for continuous driving time up front — many teams use 90–120 minutes — and double-check no driver's plan exceeds it.
4. Account for time-of-day factors
Endurance races often run through dusk and darkness. At night, visibility drops and track temperatures fall, which changes grip levels and braking references. Factor in slower lap times during night periods — a typical night factor is 1.02–1.05× (2–5% slower). Slower laps also mean time-limited stints cover fewer laps, so re-check your fuel plan for night stints and keep an extra lap of margin.
5. Pit stop timing and stack strategy
Coordinate pit stop windows to avoid traffic and maximize track position. Key tactics: stagger fuel stints so not all cars stop simultaneously; use full-course yellow periods for opportunistic stops; communicate pit-in calls clearly to minimize stationary time. Keep a live log of actual vs. planned fuel to catch drift early.
6. Race-day execution
On race day, move from planning to execution: update your fuel calc with actual lap times from warmup, confirm driver order, and brief the team on the pit window triggers. Use a live dashboard or pit board to track current-stint lap count, fuel remaining, and estimated end time. React to safety cars quickly — a well-timed caution stop can recover a lap.
Quick tip
Always carry at least one lap of fuel margin per stint. Running dry on the last lap costs far more time than a conservative fuel load.