Why fuel calculation matters in Assetto Corsa
There are two ways to lose a race in Assetto Corsa because of fuel. The obvious one is running dry — you cross the line on fumes or coast in from the last corner. The less obvious one is starting with too much: an extra 15–20 litres you never use can cost you three to four tenths per lap for the entire race. Over a 40-lap sprint, that's a full pit stop worth of time given away for nothing.
An accurate Assetto Corsa fuel calculator removes both risks. Instead of guessing "let's fill it up just in case," you carry exactly what the race requires plus a controlled safety margin. That's how every real racing team plans fuel loads, and it works the same in sim.
The fuel calculation formula
The base formula is simple:
Fuel required = (race laps × avg fuel per lap) + safety margin
For a 30-lap race in a car that burns 2.8 L per lap with 1 lap of margin:
Round up to 87. Simple. The trick isn't the math — it's getting the "average fuel per lap" number right.
How to measure fuel consumption per lap
Enable the fuel display in the Assetto Corsa HUD or use an app like RealApp or PtracKing. Do a practice session of at least 5–8 clean laps on the same track with the same setup you'll use for the race. Discard the out-lap and any lap with an off-track or mistake.
Take the fuel used across the remaining clean laps and divide by the number of laps. That's your average. Don't use a single lap — consumption varies with tow, weather, tyre wear and small differences in throttle application.
Rough consumption ranges by car class
- GT3 — 2.5 to 3.5 L per lap depending on circuit length
- LMP1 / LMP2 — 3.0 to 4.5 L per lap
- F1 / Formula Hybrid — 1.8 to 2.5 L per lap
- Road cars (Porsche, BMW M3) — 3.5 to 5.5 L per lap
- Touring cars / TCR — 2.0 to 3.0 L per lap
These are ballpark figures for reference. Always measure the specific car and track combination.
Timed races vs lap-based races
Most league races and endurance events in Assetto Corsa are timed (60 minutes, 90 minutes, 6 hours) rather than fixed-lap. For those, first estimate how many laps you'll complete:
Example: a 60-minute race with a 1:48 average lap time = 3600 s ÷ 108 s = 33.3 laps. The race ends when the timer runs out mid-lap, so calculate for 34 laps to be safe — that final lap always happens.
Then apply the standard formula. Do not use your fastest lap for this calculation — races are slower than qualifying. Add 1–2 seconds to your qualifying pace for a realistic race average.
How much safety margin to add
Margin depends on race length and format. Some rules of thumb:
Sprint race (under 30 min) — 1 extra lap. Enough for one small mistake.
Medium race (30–90 min) — 1.5 to 2 extra laps. Traffic and one safety car covered.
Endurance (over 90 min) — 2 to 3 extra laps per stint. Weather changes and multiple safety cars.
Fuel-critical strategy (undercut / overcut) — as tight as 0.5 laps if the potential gain justifies the risk.
In league racing where safety cars aren't simulated, the margin can drop closer to the sprint values. In offline races with the AI, count on the AI being erratic and take the wider margin.
Fuel weight and its impact on lap time
Fuel weighs approximately 0.75 kg per litre. In Assetto Corsa this is simulated accurately — every extra litre you carry slows you down. For a GT3 car, 10 kg of extra weight typically costs 0.03–0.05 seconds per lap. That's why over-fuelling by even 15–20 litres adds up fast over a full race distance.
This is why professional teams calculate fuel to the litre and why you should too. An Assetto Corsa fuel calculator that gets you within one lap of the actual requirement is worth several tenths per lap compared to just filling the tank.
Common mistakes when calculating fuel
- Using qualifying pace to estimate race laps — race pace is 1–2 seconds slower per lap. You'll over-estimate laps and over-fuel.
- Ignoring the out-lap and in-lap — both consume differently. On a race with a pit stop, add margin for the extra out-lap.
- Measuring consumption on a single hot-stint — one lap in perfect conditions isn't representative. Use averages.
- Forgetting the formation lap — it consumes fuel too, and it's not always a normal lap of consumption. Add 0.5–1 lap for it.
- Not accounting for weather — rain slows you down, meaning more time on track and more fuel used per race stint.
- Filling the tank "just to be safe" — the cost in lap time is worse than the cost of a slightly tight strategy in most cases.
Free Assetto Corsa fuel calculator
All of the above is exactly what SimRacing Planner PRO does automatically. You enter your car, track, race duration and average pace, and it returns:
- Exact fuel load in litres
- Number of pit stops and optimal windows
- Race lap estimate for timed races
- Fuel-per-lap consumption calibrated to your telemetry
- Safety margin adapted to race length and format
It's a one-time €12 purchase, no subscription. If you race leagues or endurance in Assetto Corsa you'll get the money back on the first race you don't over-fuel.
FAQ
How do I calculate fuel for a race in Assetto Corsa?
Multiply average fuel-per-lap by race laps, then add 1–2 laps of safety margin. For timed races, estimate laps by dividing race duration by average lap time (not qualifying pace).
Why does my fuel consumption change between laps?
Tow, throttle usage, tyre wear, weather and track evolution all affect it. That's why averages across 5+ clean laps give better numbers than any single reading.
How much fuel margin should I add?
1 lap for sprints under 30 min, 2 laps for medium races, 2–3 per stint for endurance. Never rely on finishing the last lap on fumes — traffic can catch you out.
Does fuel weight really affect lap time in Assetto Corsa?
Yes. Roughly 0.03–0.05 seconds per lap per 10 kg in GT3, more in lower-downforce cars. A full tank vs a lean load can cost you a place or two over a race distance.
Is there a free Assetto Corsa fuel calculator?
The formula above is free. For automation — including pit stops, race lap estimation and per-track calibration — SimRacing Planner PRO is a one-time €12 purchase.