whats your average gas mileage?

BeatersRus

BeatersRus

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im planning a road trip in my newest beater soon.
it occurred to me you fellas would have a realistic idea of gas mileage of a typical c body with a low comp 440.
typical car,around 3800 lbs low comp 440 auto with around 2:94 gear ratio.
ill be running the thermoquad,so hopefully? some form of 10-12ish isnt too much to wish for?
 
Average mpg for the 440 on the highway is up to 12mpg, so yes its not out of the question to get that.
 
BeatersRus said:
some form of 10-12ish isnt too much to wish for?
Click to expand...
You've got the key word correct. I have heard of others claiming better, never happened when I bothered to track mine... If you are budgeting or trying to plan fuel stops, I would calculate 10 MPG and then give a fair margin to run short with both $$ and miles.
 
Anything I'm running all get 10 or so, all BBs. My first Polara with a 318 and 276 gears would get 18 on the highway on a good day. That was when the car was still my dad's with low miles.
 
My Imp weighs 1,000 pounds more than your C-body? I get 11 to 14 on the highway and the curb weight is closer to 4,800 lbs + 2 people and a trunk and back seat full of stuff.
 
BeatersRus said:
im planning a road trip in my newest beater soon.
it occurred to me you fellas would have a realistic idea of gas mileage of a typical c body with a low comp 440.
typical car,around 3800 lbs low comp 440 auto with around 2:94 gear ratio.
ill be running the thermoquad,so hopefully? some form of 10-12ish isnt too much to wish for?
Click to expand...

On a recent trip two weeks ago to the 300 Club Meet in Geneva, NY, the "Parts Car" achieved 14.7 and 14.03 MPG after two fill ups. Its a '66 300 with a 440, 10:1 compression and a Carter AFB.
 
My 440, 413, 425 cars get 12 mpg. The 360 2bl gets 16 and 360 E58 car get 13 mpg. The 400 (Grand Prix) is unknown as I only run one tank of fuel a year thru it. All of the above are done while driving conservatively.
 
Early this month on a trip home from Mobile Alabama in jazabelle, I got an incredible 15 1/2 MPG. 300 miles at a steady 65-70 mph.
The Admiral, (318) has gotten as much as 21 MPG but typically around 18.

Fuel mileage was never a big selling point for C body's, I don't think.
 
Totally depends on your tune. If it's pig rich, or your timing is not optimized, it will suck. Try to run it in its sweet spot, where the car wants to run, not the speed YOU want to run. It should be capable of 13-14 without too much trouble I'd think. My 71 W200 power wagon got 14 running empty on the highway (3,000 rpm @ 60 mph) with 383, and 10-11 with a low comp 440. No reason your car shouldn't be at least that good with better gearing and aero.
Travis..
 
What the heck engine combos are y'all running to get such POOR fuel economy on the road? 3.91 rear gears? No stock C-body ever got that bad, even a 426 HEMI . . . when they were new. GM and Ford usually took the crown for low fuel economy, NOT Chrysler, as evidenced by the old Mobil Fuel Economy Runs, in which Chrysler products always did very well.

Our '66 Newport 383 2bbl (2.76 rear axle), which liked to run 75-90mph, would get about 17mpg when cruising below 75. On one trip in dark west TX at 90mph, it got 15mpg. My '70 Monaco 383 "N" with 3.23 rear gears would usually do about 16-17mpg on the road.

After I upgraded the old Stromberg WWC 2bbl to a Holley 2210 OEM Chrysler carb, at 55mph, I calculated that at the 55mph speed, it was getting right at 20mpg.

In '74, in the midst of the fuel crunch back then, Fenner Tubbs Chrysler (Lubbock, TX) had a demo fleet with each size engine in it, all C-body cars. They topped the tanks at the Shell station across the street from the dealership, drove south on city streets, then to the edge of the caprock, turned around and came back. Stopping at the same station for a fill-up Cruising speed, with the factory cruise control, was 55mph.

New Yorker 440, 20.66mpg Newport 400 2bbl, 20.44mpg Fury III 360 2bbl 19.66 mpg. All with probably less than 2000 miles on them.

When a GM customer came in to trade, as it had been a good agricultural year out there, they scoffed at the fuel economy hand-outs. So, "Take it for a weekend and see what you think." The Chryslers always sold on Monday, after that weekend. They sold large amounts of Chryslers out there, that year.

So, just curious if y'all are driving up hill all of the time or what? Too much cam or other things not fully dialed-in?

There were a few times the '66 got 10mpg, though. When the car airhorn on the Stromberg warped and the power piston lost the vacuum to hold it closed. Full-rich mixture all the time. That was one thing that got fixed with the Holley replacement carb. Plus better venturi design. Another time the fuel economy "dumped", the vacuum advance wasn't working.

What are y'all doing to those poor things?

CBODY67
 
Fuel economy has so many different factors, engine condition, tune, gear ratio, driving skills, city or highway, cruise control or not, that is why there is an average. Also what area of the country you are in.
Just be happy in the fact we are driving the best cars on the road and WILL pass everything out there in factory trim.
 
I never imagined I would be happy with my 62 Dart getting 10 mpg, with a +.030 440 @ 11:1 with 4.56 and an automatic , as long as I don't crack the secondaries, but that's not much fun.
 
CBODY67 said:
What the heck engine combos are y'all running to get such POOR fuel economy on the road? 3.91 rear gears? No stock C-body ever got that bad, even a 426 HEMI . . . when they were new. GM and Ford usually took the crown for low fuel economy, NOT Chrysler, as evidenced by the old Mobil Fuel Economy Runs, in which Chrysler products always did very well.

Our '66 Newport 383 2bbl (2.76 rear axle), which liked to run 75-90mph, would get about 17mpg when cruising below 75. On one trip in dark west TX at 90mph, it got 15mpg. My '70 Monaco 383 "N" with 3.23 rear gears would usually do about 16-17mpg on the road.

After I upgraded the old Stromberg WWC 2bbl to a Holley 2210 OEM Chrysler carb, at 55mph, I calculated that at the 55mph speed, it was getting right at 20mpg.

In '74, in the midst of the fuel crunch back then, Fenner Tubbs Chrysler (Lubbock, TX) had a demo fleet with each size engine in it, all C-body cars. They topped the tanks at the Shell station across the street from the dealership, drove south on city streets, then to the edge of the caprock, turned around and came back. Stopping at the same station for a fill-up Cruising speed, with the factory cruise control, was 55mph.

New Yorker 440, 20.66mpg Newport 400 2bbl, 20.44mpg Fury III 360 2bbl 19.66 mpg. All with probably less than 2000 miles on them.

When a GM customer came in to trade, as it had been a good agricultural year out there, they scoffed at the fuel economy hand-outs. So, "Take it for a weekend and see what you think." The Chryslers always sold on Monday, after that weekend. They sold large amounts of Chryslers out there, that year.

So, just curious if y'all are driving up hill all of the time or what? Too much cam or other things not fully dialed-in?

There were a few times the '66 got 10mpg, though. When the car airhorn on the Stromberg warped and the power piston lost the vacuum to hold it closed. Full-rich mixture all the time. That was one thing that got fixed with the Holley replacement carb. Plus better venturi design. Another time the fuel economy "dumped", the vacuum advance wasn't working.

What are y'all doing to those poor things?

CBODY67
Click to expand...
I have 3.55 gears, 275/60/14 tires and keep it at 2750-3000 rpm or below, and I'm guess I get around 10. 440 out of a later 70's barge, Edelbrock Performer and 750 AFB, MSD box, tti headers exhaust out the back. I thought I was getting 15 or better, but then I realized the gas tank was 10gallons larger than I thought.
 
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