Gaijin models vehicles based on history, not preferences.
You need to learn fuel management, which is key in air battles. Take too little, you run out of fuel before you reach the battle, take too much, you lose turning rate.
But in case of J7E and J8F
They acually used fuel tanks of course,
In game, You have to reduce fuel using as many as you can
26minute fuel with WP-13 engine is very painful