Total fuel for endurance race!

Total fuel for endurance race! Eg 3 hours VRS enduraance Daytona. 102 laps = 330 Liters First stint is with 104 it will calculate the fuel needed for remaining race. Bonus: It will calculate the minimum fuel needed when wanting to change all 4 tyres while also not losing time in pits . Fx: 4 tyres = 30 seconds., but after 2 stints you want new tyres also. if you fuel 104, 104, and 30 you wont have time to change tyres. but if i do 90, 90 and 50 i will. So a condition would be to change 4 tyres always? The most important is the total amount of fuel for the entire duration with more than one pitstop.