The best fuel consumption I have ever had was on the back of the AA truck.....90 miles and no usage!!!!
Float valves can get sticky. And cure the drip because not all of that petrol goes out of the exhaust . Some of it is compensating for oil loss in a bad way. Whatever drips when the engine is stopped does not make soot, it creeps past piston rings into the oil. Fix it or lose it.
As you can see is this highly tactical scientific drawing, shows. The amount of time that was invested in the aerodynamics of these buses. about The same time you could have a beer and a smoke . Including laughter ..
Yes but that's your lightweight US gallons Here's what I did to my bus today. I whipped the top off the left hand carb. The float valve didn't seem to be projecting far enough down into the chamber compared to another valve I have so I've swapped them over. I couldn't be more scientific than that since I don't know how to measure the valves. It's stopped the drip on the accelerator pump tube though. I'll do the other side tomorrow.