for those that have been acheiving, self repairing, DIY..I need not say much.
I got my first hints of 35mpg on an old dodge omni, 1980s. A friend could not get it to super stoich. Blamed all the obvious, even the carb. Lucky for him his father, the ASE by career, went about too many things to even remember how precise that had to get, to truly have 35mpg. One error in anything and it is 5-10mpg loss.
I mention this with just one recent error I found on my old 22 year project. A gas filler tube, stainless stell, broke clean off at the rubber hose going to the tank...The cause? you wouldn't believe it if I put it into plain laymans term english.
It reminded me of physics that go with 40mpg. There are sections of system that are so slow, you would think it has no function. the carb whistles invisibles. It is so slow in the fuel consumption, the fuel vent becomes fuel mileage...
Anybody else have some physics stories with 40mpg? The real thing is very very intense. I did learn alot over the years, and funny enough most emission standards hinder fuel. I found the convertor, and fuel vent system (charcoal canister) was the only things emoissions related that truly helped. Removing EGR doubled my fuel mileage...