Hey i know most additives do very little in the way of improvements when it comes to fuel but i had some lucas fuel additive and it did improve mileage. My next question is can i add regular motor oil such as a 10-30 or even a 30 weight to my gas. My 96 Nissan maxima has over 250k and i have done no motor maintenance other than plugs and oil and filter changes. The lucas did improve my mileage but was it because it just thickened up my fuel and my well worn injectors like the thicker mixture? Also if i can not use a motor oil would a 2 stroke oil work? I understand that i will need to dilute these down a lot i was thinking in the 250 or 300 to 1 ratio's i'm hoping that a dilution this thin will not foul plugs. I know my car needs certain sensors such as both o2 and probably a new pcv valve so i'm not worried about trashing those. Also i dont want to become a super polluter but i have no emissions where i live so that is not an issue. So if anybody has any advice or tips or dilution recommendations please let me know thanks ya'll