I didn’t see it mentioned but I assume the engine reliability is still recommended at 30, right ?
not sure if the calculation wrong or i did it wrong somewhere when calculating the racing fuel economy, even when i using packbat data
for some reason im always get larger result not even close to 1185 value
@Denta: What value are you trying to get? If you multiply all the numbers together, you should get some number of kilograms of fuel, probably between 50 and 150.
I cannot speak for the MR people but I know that I built an FR with a 50-50 weight distribution so fuel weight shouldn’t affect its handling too much
Last I heard fuel weight was added directly to the center of mass - has that been changed?
(Also, fuel weight does not lower effective ride height.)
An engine reliability of 30 should be okay and fuel is added to the center of mass, not changing handling.
let me confirm my calculation using your data sample, what i do is
1.5 * 523.85505501344005 * 135.65301510020001 * 1 * 0.75 = 79945.3323991thats not even close to 118.5kg
^you forgot to divide by 1000. So 80kg of fuel for you
Right - thank you, AirJordan.
80kg is probably a good point to be at - I expect you can complete all the races with one pit stop.
I have no idea how you guys are getting data for fuel calculations but I suspect it means opening up a .lua file. There has to be an easier way! 
thanks guys, now waiting for tyre wear calculation
[ul]]Convert peak power to kW at 1 hp = 0.7457 kW if necessary. (In this case, 158 hp = 117.8 kW.)/:m]
]At peak power RPMs (i.e. the same position on the horizontal axis), estimate the position of the fuel economy line between the gridlines of the economy graph. (In this case, about two-thirds of the way up.)/:m]
]Interpolate using the numbers on the left side of the chart. These numbers are always measured in g/kWh, even when the number on the chart is lb/(hph), as here. (In this case: 650-350=300, 2/3300=200, 350+200=550 g/kWh.)/*:m]
]Multiply the numbers together to get kilograms. (In this case: 1.5 h * 117.8 kW * (550 g/kWh / 1000 g/kg) * 0.75 = 73 kg.)/:m][/ul]
I think you can get the footprint of the car from the chassis morphing tab (edit: nope - you have to make a new car with the same body and measure it that way - it’s the first and third numbers, I think), but I keep forgetting and looking for it in the .lua file instead. (If you’re using feet, 1 sq. ft. = 0.093 sq. m.)
And what is “r” again?
1.5 hours
182.8kW
~600 g/kWh
134 width x 233 wheelbase?
“r” is the fudge factor. It varies a lot based on factors I haven’t nailed down, and it definitely varies based on track.
[ul]
]A car which is on the high end relative to my formula would use something like 0.61 on ATT (a low-consumption track) and 0.75 on Norisring (a high-consumption track)./:m]
]The median car uses from 0.52 (ATT) to 0.64 (Norisring)./:m]
]The low-fuel car uses from 0.44 (ATT) to 0.53 (Norisring)./:m][/ul]
What I did was design around r = 0.75 with the assumption that I’ll be using 20% less than that on ATT.
Edit: Is it wheelbase or total vehicle length? I thought it was total vehicle length.
I thought so too, but the only “length” I can find is WheelBaseLength=233.05786895751953. I also found this:
FootPrint={
164.06199645996094,
412.8040771484375
EDIT: OK, I have it now. 1.64m x 4.13m x 7 = 47.4 which means I have 47.4kg capacity in my fuel tank?
Yeah, that sounds right. And if I’m running the numbers correctly, total race fuel consumption is 123.3 kg - so two stops.
Yeah, I think I have it now. Thanks for explaining it so I could understand. I’ve never really thought about it this deep before. 
Glad to be of service! Just wanted to reduce the guesswork going into the process.
Results are delayed as I found another small issue which needs fixing first. Maybe during the weekend then.
Aaagh! 
Better to fix the bug than display misleading results, though. Thanks for the heads-up.