Seem to remember an interview on Radio LM last year reference the bio fuel car. If I remember correctly there was a discussion to the effect that they needed to be allowed a larger fuel tank to compete, due to the lower calorific value fuel that they where using, but had to use a tank the same size a petrol engined cars, which hampered them.
If the difference between diesel and petrol in mpg and tank range is of the same order in race cars as in road cars, then there might be a hare & tortoise scenario.
Need mpg, tank size, lap times and a pencil and paper to work it out.
However tyre life would also come into the equation.
Could be intresting
