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

[Topcat]

My engine ran remarkably well on fuel consumption this last hot week-end.
Went on a long drive and gas gauge stayed pretty steady.

Running a little higher Octane certainly helped.

I estimated my Hemi was getting around 15 MPG.

Would like to hear how you all are doing on long cruising gas mileage.

[cuda dad]

700 mile round trip the 'cuda 340 got 13.5 (estimated) w/ 3.23's 727 on 14" and the AAR got almost 12 (estimated) with 3.91's 4-speed.  It probably improved a bit once we fixed the fuel leak.

[Cuda Cody]

I'd be surprised if I get 10 mpg.  And with the small tanks on the E-Bodies it seems like a stop for fuel all the time. 

[ec_co]

shouldn't we be measured in Smiles Per Gallon?

[Brads70]

Under optimum conditions I was getting 17MPG's , now that I went from 3:55 to 4:10 .... not sure yet but I'd expect a drop?

[Jay Bee]

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

[Shane Kelley]

Can't remember what my Cuda got but my 71 Road Runner averages 7.5-8.5 mpg. Cuda probably similar. That's mostly highway. 340 with a huge cam, Quick Fuel 650 vac secondary carb and Edlebrock RPM heads with 3.55 rear gears. Automatic transmission with a 2800 stall converter.

[chal340]

13.5 mpg on the highway at 85 mph. 416 CI, 750 Dp, 3.73 rear end, 727 with gear vendors and 26" tires. less on the city 

[Shane Kelley]

13.5 mpg on the highway at 85 mph. 416 CI, 750 Dp, 3.73 rear end, 727 with gear vendors and 26" tires. less on the city 

Damn good numbers for that combo!

[Cudamike]

last time I calculated, it was 10 miles on the way out and 7 on the way back.  440 with 500HP.

[JS29]

My speedometer is fast, I think I am about 12, country driving, non ethenal hi octane. AND I STAY OUT OF THE 4 BARRELS. 

[Chryco Psycho]

As I recall the best I have done with a 440 Challenger 3.23 gears 727 auto was 23 MPG at 70 mph  [can gallon]
the other remarkable one is a 67 Coronet R/T 440/512 A833 OD Dana 3.54 making 398 RWhp /460 ft lbs tq doing 17.8 @75 mph [can gallon]

[Shane Kelley]

As I recall the best I have done with a 440 Challenger 3.23 gears 727 auto was 23 MPG at 70 mph  [can gallon]
the other remarkable one is a 67 Coronet R/T 440/512 A833 OD Dana 3.54 making 398 RWhp /460 ft lbs tq doing 17.8 @75 mph [can gallon]

Those are some really great numbers.

[Chryco Psycho]

Thanks 
Honestly it comes down to 2 things
Using a very good carb such as Proform & taking the time to fully tune it , I am not talking baout an hour or two but days tweaking every circuit
& the second is some very innovative porting in the heads creating clean flow , high velocity & as much swirl as possible to mix the air fuel very well
Making the engine as efficient as possible both in peak power & economy
Both of these engine were running stock iron heads not aftermarket alum as well .

[Chryco Psycho]

I'd be surprised if I get 10 mpg.  And with the small tanks on the E-Bodies it seems like a stop for fuel all the time.

Tougher to do with all stock parts
Next time i am up there I should port a set of heads for you & tweak the crap out of  carb & see what that does !!
An engine can still look stock but it doesn't have to perform stock !!