Motorsport Tools

Race Fuel Load Calculator

Plan your fuel load for sprint runs or circuit races. Avoid carrying dead weight while keeping a safe margin - and check the ballast impact if you're running close to class minimum weight. Race fuel at £3-4/litre makes over-fuelling expensive; under-fuelling is worse.

Fuel & Consumption

Typical sprint run: 0.8-2.5 L
Recommend 10-15% for sprints
Pump E5/E10: ~0.745 g/cc Race petrol: ~0.755 g/cc 101 Octane: ~0.758 g/cc E85: ~0.785 g/cc Note: density varies with temperature - these are at ~15°C

Circuit Race Event

Enter race duration and your expected lap time - the calculator works out how many laps you'll complete. Qualifying is entered separately as you'll refuel between sessions.

Race
Scheduled race time, not including formation
Use your qualifying or practice best + 2-3 sec
Calculated at full race consumption - formation laps use ~50% less, absorbed into safety margin
Buffer for last lap / yellow flags
Estimated race laps: -   
Qualifying (separate fuel load)
Typical 2 laps for out + in
Est. qualifying laps: -
-
Litres to load
-
Fuel mass (kg)
-
Total runs
-
Fuel cost (£)
Weight Planning

Post-Race Weight & Ballast

Scrutineering weighs you after the race - so what matters is car + driver + remaining fuel at the flag. The remaining fuel is the safety margin you built in; the race fuel itself will be burned. If you're tight on minimum weight, loading more fuel than you need actually helps you at scrutineering.

Vehicle & Class Data

Dry weight - no driver, no fuel
Include helmet & suit
-
Weight at start (kg)
-
Weight at flag - scrutineering (kg)
-
Margin over minimum at flag
-
Ballast adjustment (kg)
Post-race weight vs class minimum (scrutineering)
Under minimum ✗ At minimum +5 kg +10 kg+
Cost Planning

Event Fuel Cost

-
Fuel load cost (£)
-
Cost per run (£)
-
Effective cost/litre check

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