I am looking into getting a dodge m37 and would like to make it in to a daily driver but want to find out how i can get better fuel mileage with the original 230 engine. I have looked into an engine swap and have found a few engines that could help with fuel mileage but i want to see if i can use the original 230 engine. I allready plan on wanting to change the gear ratio for higher speeds, and am not even sure if the 230 engine will do allright with what i want to do. Any help would be muchly appreciated.