Cars taking part in 'economy races' achieve almost incredible mileages?

I am interested to find out how to get better mileage from my 190E MB (1800cc), used to be 6-7km p litre, now 8kmpl after changing a faulty fuel distributor.Cars taking part in 'economy races' achieve almost incredible mileages?
Driving style is the best way, of course. Treat the pedal like its an egg you don't want to break.



Decrease the weight. Remove all non-essential items. That will help.

Low resistance tires will help as well. You probably should change the plugs as well on a car that old, as well as all filters. That would help. You could try replacing a stock filter with a K%26amp;N free flow air filter as well.Cars taking part in 'economy races' achieve almost incredible mileages?
Take out the gas engine and install a diesel, as well as a high geared rear axle.