|
With an automatic you can expect 26.5-27 mpg if you keep your speed under 65 mph or 2500 rpms. Pumping your tires up to 36-38 all around will help. Before mods on my 87 745T that was the best I could do. Now I get regularly 29.5 to 31 highway. But I also swapped out the auto for a M46 manual as well as lowered the car and swapped out the rear end for a 3.31 ratio unit. I filled the engine, transmission and rear end with synthetics. The type of engine oil has the least effect on gas mileage. Mineral or synthetic are pretty close in efficiency but 5W30 will get you slightly better mileage than 10W30 oil.
|