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How much time does 1L fuel slow down a car?

Question for iGP developers:
How much time (on average) does 1L fuel slow down a car in a lap?

Suggestion:
It would be nice to test a car with new set of tyres and different fuel L:
1 lap with 45L
1 lap with 44L
The [time difference] would provide [sec/L] an example how much time 1L slows down my car and help me plan better my strategy

Thanks,
Malgo

But then you are assuming the driver performs perfectly for those 2 laps, and they programmed in driver to make errors in practice, which is why the lap times fluctuate.

Now if someone was dedicated they could record their driver's stats and all practice lap times to see if there was a con distant Delta on the times and what driver stat changed it....

you have 2 drivers so you have 10 test runs

do one driver as normal
save
go to the car and change supplier to +1 Fuel
then do the test runs of other driver and compare lap times.

Most likely no noticeable change

fair point. I would like to know whether iGP can disclose this info:
How much time (on average) does 1L fuel slow down a car in a lap?

I don't think that would work James. The +1 supplier affects design stats and not fuel weight. But if we could ever get rid of all the dead IGP accounts it would be great to have practice runs using the race viewer with the same stats we get when we race. We could run our drivers and reserves against each other and really get good data.

They might tell but on some tracks and in the wet the extra weight is faster not slower

As for what I said above it doesnt use much less fuel

Top is 1point Fuel with +1 Fuel supplier
Bottom is 1point Fuel

james, that info provides required [fuel / lap] which is improved with your trick. it does not provide info on how slower a car is with +1L of fuel

It isn't possible to answer, if you think about lap lengths between Monaco and Spa then at Spa you're carrying that 1 ltr for much longer.

Every track will be different.

I use the assumption 10 to 15 ltrs as being around 1sec on a clean lap which works for me.

Multiple accounts are allowed, there's nothing to stop you having a test team to see what works for you.