Not a spreadsheet you fill in before the race — Race Engineer reads your actual fuel burn from telemetry and recalculates every lap, all through the session.
Most fuel calculators ask you to type in a lap time and a consumption figure once, before the race starts. Race Engineer instead reads iRacing's telemetry SDK continuously and measures your actual fuel used each completed lap — so the number adjusts itself as you save fuel, hit traffic, or the stint runs longer than planned. You never re-enter anything mid-race.
Every lap, Race Engineer recalculates fuel-to-finish from your measured burn rate: laps of fuel remaining, total fuel required to the checkered flag, whether you can finish without stopping, and — once a stop is needed — exactly how much to add. If more than one stop remains, it fills to the brim and leaves the final-stop amount for later, matching how real strategy is planned.
Race Engineer keeps several fuel-per-lap estimates at once — a session average, a recent-laps average, and a weighted average that favors your latest laps — and cross-checks them against the car's own fuel sensor. A single bad reading gets caught instead of driving the whole strategy off course. Confidence is reported honestly too: Low, Medium, or High, based on how many valid laps have actually been observed.
Every prediction keeps a fuel margin above your measured need — never less than half a lap's worth, whatever else is configured. The final pit stop of the race gets extra margin on top of that: being short on an earlier stop self-corrects at the next one, but a short final stop means an unplanned emergency stop with no laps left to fix it. That distinction came from a real 2026 race where an exact-to-the-liter final stop cost five track positions.
When the numbers say you're short, Race Engineer shows exactly how much fuel-saving would close the gap — and whether that percentage is realistic, capped at a 15% ceiling. It's a concrete target, not a vague "try to save fuel" reminder.
Yes — you don't enter anything before the race. Race Engineer measures your actual fuel used lap by lap from telemetry and recalculates continuously, instead of projecting from numbers you typed in once.
Confidence is reported as Low, Medium, or High based on how many valid laps have been observed — it starts Low on lap one and reaches High once enough clean laps have been recorded, rather than claiming full confidence immediately.
A lap with a usable fuel reading — a pit lap, an invalid sensor reading, or certain off-track laps can be excluded so a single bad lap doesn't distort the average.
No. Every prediction keeps a minimum safety margin above your measured need, and the final stop of the race gets extra margin on top of that — the margin never drops to zero, regardless of settings.