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How to Make Fuel Calculations in Iracing

Learn how to make fuel calculations in iRacing: simple steps to measure fuel-per-lap, set pit strategy, and avoid running out of fuel — fix this now. Act now.

If you’re asking how to make fuel calculations in iracing, the short answer: measure your actual fuel burn at race pace, multiply by the number of laps left, and add a safety margin. You’re in the right place — below is a fast, practical method you can do inside iRacing now.

Quick Answer

Measure fuel-per-lap in the same car and conditions, then use: fuel required = laps remaining × fuel-per-lap + safety buffer. Set that amount in the Garage fuel box before the race or pit stop.

What’s Really Going On

iRacing doesn’t magically know your exact race burn because fuel usage changes with throttle/braking, drafting, track temp, and tyre wear. The simulator gives estimates, but the safest method is to record the fuel used when you drive the car how you will in the race (race pace, same fuel load, same draft/no-draft). That real-world number is what you use for calculations.

Step-by-Step Fix

  1. Run a short fuel check: do 5–10 laps at the pace you expect in the race (same fuel level if possible).
  2. Check fuel used: open the Garage > Fuel or use the session telemetry to see how many liters/gallons were consumed over those laps.
  3. Calculate fuel-per-lap: (fuel used) ÷ (number of laps run). Example: 6.0 L used ÷ 5 laps = 1.2 L/lap.
  4. Multiply by laps remaining: if the race is 30 laps and you’ll start with full 30, use 30 × 1.2 = 36 L. If pitting, use laps of the next stint.
  5. Add safety buffer: add 1–3 laps worth (multiply fuel-per-lap by 1–3) depending on race length and risk of cautions/drafting. Example final = 36 + (1.2 × 2) = 38.4 L.
  6. Enter fuel: in Garage > Fuel, set the fuel amount to the rounded result (iRacing shows the entry box). For pit stops, set the fuel you want to add in the Pit Stop Strategy. Save and verify before going green.

Extra Tips / Checklist

  • Use the same conditions: fuel burn differs with drafting, hot track, or pushing hard. Match practice to race.
  • Short tests beat guessing: 5–10 laps at race pace is enough and fast to do.
  • Trim weight vs. safety: less fuel = faster laps but higher risk of running out. For sprints, 0.5–1 lap buffer; for long races, 1–3 laps.
  • Watch iRacing telemetry: fuel trending downward gives better precision than the session estimate.
  • If drafting is common (oval packs), anticipate 10–30% lower burn when in a tow; don’t rely on drafting for your base calculation.

FAQs

Q: How many laps of safety fuel should I add?
A: For short races add 0.5–1 lap; medium 1–2 laps; long endurance 2–3 laps. Increase buffer if pit timing or cautions are uncertain.

Q: Should I use iRacing’s estimated fuel-per-lap value?
A: Use it as a starting point, but verify with a short race-pace run. iRacing’s estimate can be off due to driving style and draft.

Q: How do I set fuel for a pit stop?
A: In Garage > Pit Strategy enter the fuel amount to add for that stop. Use the same calculation for the next stint’s laps remaining.

Q: Does fuel burn change with tyre wear or track temp?
A: Yes. Expect small variations; repeat a quick burn test in similar tyre and track conditions if you can.

Wrap-Up

Don’t guess—measure. A 5–10 lap race-pace test, a simple division for fuel-per-lap, and a sensible safety buffer will keep you on track and off pit-road unexpectedly. Next session: run the quick test, set fuel in Garage, and you’ll avoid the costly “out of fuel” DNF.