i got a 75cj 5, i love evrything about it, except the 8 miles a gallon im getting. is this typical for the v8? or is there something that i need to get adjusted? and does anyone know around how much it will costs to go from the carb. to fuel injection?  

8 Miles to the gallon is about what my Jeep gets also.  It is about right for a v8.  As for the fuel injection there are alot of nice kits out there for around 2000 dollars.  But if you don't mind used you might want to try ebay to get it cheaper.  

My '77  '7  with stock 304 & TH400  in 2x

got 11.1mpg on the freeway once.

On the flipside offroad, in 4X low I clocked it at 4.5mpg

Well, ya gotta realize that these are special purpose machines, not hi mpg commuters. They weigh alot for thier size cuz Jeep built 'em with IRON not plastic like econo boxes are.

There really isn't much you can do. low restriction intake & exhaust.

Take off yer mud tires for street driving and go easy on the go & stop pedals because as you know ...

MPG depends upon how & where you drive...

~hope this helps~