overdrive for a ramcharger

ok it's all about L\km eh... ok mpg. my 87 ramcharger is  a pig im getting 8-9 mpg with a 360. ive got the warn premium hub.s an elcectric fan, edelbrock performer intake with a 650? cfm edelbrock carb.  new plugs cap rotre wires. both picups in the distributor and not to aggresive of a tire. 31" cooper mudterrains. my nearest wheeling place is 220km away, or 150+\- miles. i cant wheel if i cant get their. any ideas..  

what is your gear ratio and what transmission do you have. you might want to look in to a different transmission like an overdrive transmission.  

Well for starters you have wrong carb. You only "need" a 500 to 550 tops here and to big of carb reduces mixture velocity though bores which reduces mixing of fuel and air. A smaller intake with smaller runners would help too.You need to deal with this before you consider a OD tranny (which would be better than a add on OD unit too) Bigger is not better with carbs, especailly in MPG department. You might look at your timing curve and advance it more and use 89 while doing it. Dodges of that era use retarded curve which makes them not fuel friendly. Also you want to run tires at of near max pressure and load range C tires at 50 PSI roll easier as does smoother treaded tires consumes less power.The 360 is not a bad motor but it can be a very thirsty one.  

holly i didn't know that hole bit about smaller runners. i dont quite get the idea about smaller is better but i'll check it out. if new intake and carb are in order, what about an aftermaket fuel injection system i think its close in the cost. oh and im trying to figure out which tranny it is but the gear ratio is 3.77. i'm pretty sure. thanks  

Do not feel bad, a lot of people do not understand about carb size. They think a big carb is like putting a mini turbo charger on engine. It does not work that way. Ideally you want carb to reach it rated peak flow rate at HP peak RPM or a bit lower. A 4 BBL 500 CFM carb does not stop flowing at 500 CFM as it will flow well beyond that. It is just that at its "rated" capacity it has a pressure drop across it of 1.5 inches of mercury or about .75 PSI. This pressure drop and velocity through bores it important to proper fuel atomization and mixing and smaller runner promote higher velocity in them to aid this and also increases turbulence in cylinder as it fills further mixing fuel and air for a better burn. Lacking this you have to run richer to make up for fuel that does not mix with air in weaker Air/Fuel ratios and does not burn and MPG goes down. With to big of carb and a big intake you have the worst of both worlds at lower RPM and cruising. With TBI injection, it is more like a electronic carb because it induces fuel same way but more accurately for mixture control but it still needs to mix. With MPI or multipoint/port injection, the fuel is injected at 60 PSI or so with helps vaporize it better. When you are looking for better MPG, you want smaller runners and smaller carbs/TBI units generous timing curve, 89 octane fuel and no big duals because they do not work as you think either at times