What kind of fuel MPG are you getting on your engine?

[70/6chall]

I figured out on my '70 Challenger, SL6 with a 904 (Auto) and 8 3/4, 3.23's about and I believe the weight factor 2800-3200#, 14", 60 series tires, 2 barrel, dual exhaust at 65 MPH, comes in at 18.5 around town stop and go. On the freeway 21-23 on 87 octane. Surprising for a heavy car.     Thanks,   Al

[bentpshrods]

  Last summer I went to a car show in eastern Idaho--about 350 miles round trip. Running 85---100 mph both ways, with 3.55 gears I got just over 9 mpg.  Really need to fix my broke fuel gauge someday.   

[Brads70]

Hey Brad, just for clarification, is that 17MP US gal or Imperial gallon? (17mp/Imp. gal. = 14.2 mp/US gal)

Just over 300 miles on a tank, 300 divided by 18 gallon tank.   So whats that US gallons? 

[ec_co]

The U.S. liquid gallon is defined as 231 cubic inches and equates to approximately 3.785 litres. One imperial gallon is equivalent to approximately 1.2 U.S. liquid gallons.

[GoodysGotaCuda]

I'll be annoyed if I can't eek out 20mpg on the highway with my new setup. The 318 got about 10mpg, on the loud pedal quite a bit.

[Jay Bee]

Just over 300 miles on a tank, 300 divided by 18 gallon tank.   So whats that US gallons? 

Yup, that would be US, an 18 gallon US gas tank =  15 Canadian (Imperial) gallons. That's awesome mileage, now with those new gears..........

[soundcontrol]

My Challenger did great (before the teardown) with the 340 / 727 and 2.96 (or is it 2.93?) in the rear I got 18-19 MPG cruising at 55-60MPH. Brand new Holley Street Avenger and electronic ignition. Way more in city traffic though.

[71vert340]

 The best I ever got with my 71 vert 340 4 speed, 3.23 was 22 mpg at 60 mph going from Kennewick Wa. to Portland Or at 60 mph and keeping my foot out of it. Usually, 17.5 to 18 mpg. I'm on a trip right now with the 2015 Challenger R/T 5.7 and averaging around 27 mpg at 75 - 80 mph. Best with it was a 4600 mile trip last Sept to the Midwest and averaged 29 mpg until I got back to the mountains. Then for the rest of the trip, I finished at 27.2 mpg
Terry

[Brads70]

Funny common theme here is " when I keep my foot out of it" 

Tough thing to do with these cars for sure! 

[61K T/A]

I never really gave it a though about my MPG. I'm always thinking about how I can burn more fuel.     

[rhamson]

  Last summer I went to a car show in eastern Idaho--about 350 miles round trip. Running 85---100 mph both ways, with 3.55 gears I got just over 9 mpg.  Really need to fix my broke fuel gauge someday.   

I used to count my mileage with my old car that got 6 MPH. I got caught once short by a mile and that motivated me to fix the gas  gauge. I hope you don't have to walk a mile in my shoes.

[RUNCHARGER]

Ha, ha. I remember I was driving my 69 Hemi GTX 200 miles to a job some years ago. It was getting phenomenal gas mileage but was pinging on the hills. I had a look and the distributor had moved a bit and it was advanced about an extra 10 degrees. I think I got near 20 MPG that trip.