When my "new" truck was down I drove ol' reliable to work everyday (50mi ONE way) Thats when I was gettin 12-13(YAY!) doin about 60mi the whole way. I'm not sure on the RPMs since the truck dint come with a tack, but it is straight piped and it doesnt sound like it was racin too hard, if i had to guess i'd say around 2k, but thats jus what it sounds like, really no idea. My speedo goes to 80, i pegged it once so idk how fast it was goin, but the motor was running PLENTY fast, i just had to see what she could do

 

I have a 96 Dakota, 2.5L. I just got this last week and My first tank of gas measures about 19.5mpg. BUT I just replaced the exaust manifold gasket 2 days ago because it was leaking, And just found out my Post-Cat O2 Sensor is broken. I will report back as soo as I get the O2 Sensor in.

 

Man If i try I can get 18mpg with my 90 d150 with a 318.

 

Thats what the guy that sold me mine said too. I think i still wouldn't break 16 if I put it in neutral with the engine off at the top of a mountain, and fred flinstoned it down.

 

i think it could be possible. i think with an rv cam in a practically stock 318 with a fairly decently tuned carb it could get 18mpg. my 81 has gotten 15mpg and i know my carb needs to be tuned.

 

OK Just put in My O2 Sensor in tonight. I am at 3/4 of a tank so I am gonna let it ride and see if the average goes up. After reading some posts on here, most all say you can improve your gas milage by up to 40% by replacing a defective O2 Sensor. We will see.

 

With 30 inch tires (recommended in door jam), I got consistently between 10-12 MPG combined with mostly in town driving. Now with the 33 inch tires, the math is horrible, but i know the it only looks bad. Bigger tires require bigger gears to compensate.

 

My new tranny doesn't have a lockup converter, but I still got 14 mpg out of my last tank, and that was running it pretty hard. Funny thing is I drive it like an old lady and only get 15. Maybe I need to find a "somewhere in the middle" driving style for the best results.

 

I have a 91 RC with 360 auto trans 4X4 and was getting about 8-10 and the spent 550 on a heavy duty cat with a 50 series flow master exhaust and gained a noticeable amount of increased power and gained about a extra 50 miles a tank of gas. Was amazed!

 

12-14 in town. 360 bored .040 over .422 .442 cam 650 carb and headers flat top pistons an some small head work. 315/75/16s with aluminum wheels. 4in lift.

don have a lead foot and dont try to race the riceburners!