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Fuel Speed

How much slower do you go if you add on an extra litre of fuel to your car?

About one kilogram i reckon

So you go one kilogram slower?????

The speed you loose because you drag around one more kg. 

Yes but how much time do you lose? E.g ( this is made up but ) you lose 0.2 seconds pure lap when adding on an extra litre of fuel.

Don’t know mate, i was just guessing really. To answer your question, i think it will differ per track plus take into account push level, which in itself is dependent of track temp. 

Your asking the wrong question Banter...due to fuel economy, track length, push levels, timing of racing circuit in the calender. The question should be...How do I make my car as quick as possible with my current car design points and use lighter / normal / heavier fuel loads depending on push levels and temps at each individual circuit in the racing calendar for the perfect strategy / setup I can currently achieve with the cards I've been dealt? ? Re-read this a few times to let it sink in ?

Yes, banter, yes ???

I guess I wanted a simple answer to a complicated question.

fuel economy does not work, at the end of the season when the B4 is already 200 and the fuel is top, you fail the qualification with a Bang,and on the track if you are heavier, you go at the same pace with the lighter ones, checked repeatedly(((