How to edit fuel usage in ENG files

Hello, I would like to learn how to edit the fuel usage of an engine file so a car can use more or less fuel. I'm using the IROC 9606 mod and I find that the car uses about double the fuel of the real car, so I want to try to get around the same fuel use as the real car so I can do real race lengths with no pit stops like the real cars did. Can anyone explain to me how to calculate these variables?

Here, I'll put an example that I want to test with. They did 40 laps at Daytona on the oval with no pit stops. I would like to achieve this.

i think it's
FuelConsumption=2.8e-5 (for example)
in eng file
(2.8e-5 = 2.8 x 10-5 = 0.000028)
you can use both notations
so i would put 0.00001 for a clio and 0.000095 for a big suv
am i right?

Legicide12 wrote:

Here, I'll put an example that I want to test with. They did 40 laps at Daytona on the oval with no pit stops. I would like to achieve this.

I might be getting your request all wrong here but, if you alter the consumption of one engine then other cars in the same class without that engine will/may be at a disadvantage, what I mean is if you're gonna' do one then you should do em' all or at least look at them.
On the other hand, you could turn off fuel usage and or tyre usage in the options "Realism" tab