Gas Milage in EB

[nvrstuk]

Interesting how a semi-stock 302 with 165hp gets worse mileage than a 500hp stroker on 40" tires... something about efficiency... lol

I need to roll the 460 for a several hundred mile trip when the weather gets better, see if I can break 12 with it...

 

[EricLar80]

EFI, a little tuning for efficiency, and an overdrive will go a long ways. You can tune for efficiency without loss in power, it's just a matter of leaning out cruise.

 

[nvrstuk]

That's what OE is going for...mpg and emissions compromise. They need every mpg for raising their average mpg ratings to meet federal standards...

 

[bmc69]

Best I ever got was 15 mpg ...69 3 speed 250 i6 on 33s. My near bone stock 68 3-speed was second...got about 13. The rest seem to average 10-12.

 

[bronco1017]

I tell people mine is good on gas.
It uses every bit I put in it.

 

[ep67bro]

10-14 on the highway depending on how I drive it. Thats a 289, holley carb, NP-435 trans, 3.50 gears and 35s. It was a little better on 33s. I have the 23 gallon tank so MPG is not much of an issue.

 

[sprdv1]

You're doing good.
These things are as aerodynamic as a cinder block.

I used to get similar mpg when I was set up your stock 2 barrel way.

Fuel injection will get you better mileage but as you know its not waaay better. But fuel injection is still an excellent upgrade as other things improve like drivability and the elimination of vapor lock and percolating fuel in the carb bowl.

for sure... Never have tested mine on mpg cause it ain't on the street enuf..

 

[blubuckaroo]

This came in the glove box when we bought our '77.
I believe you could get these numbers, with a totally stock Bronco, if you were very, very careful and on a long flat road.
Of course, for most of us, hypermiling with these things isn't realistic.

 

[gnsteam]

I do remember getting 14-16 with the totally stock 75, with 302 auto and 3.50 gears. This was back in the 1983-86 timeframe.

 

[jim3326]

I saw the title of this thread and thought.... "Those 2 things don't go together!";D

 

[Mikesimp70]

My wife has a VW Atlas. She says every time I drive it I destroy her mileage. I only drive it when we go out of town so is more highway driving. She gets 24 and I get 19.

Im the only driver for the Bronco ...I get 12+/-. 302, FiTech 411, 4R70W 31s

 

[EB70]

Stock 70 with a 302, headers and a 2-barrel. 3.54 gears with a 3" lift and 33's got 16 MPG. I drove it like a baby on a work trip at 55-58 MPH. Same truck with 37" toyo MT's and 4.56 gears got 12-ish. Maybe 13. Had to drive a little faster because they raised the speed limit.

 

[Qumanchew]

Keep in mind, unless you've verified that your Speedo is correct, like with GPS, you have no idea what for mileage your actual getting.

 

[nvrstuk]

Keep in mind, unless you've verified that your Speedo is correct, like with GPS, you have no idea what for mileage your actual getting.

That is what I keep saying over and over... and over...

... and test the mileage over several hundred miles, not 50

... and fill up at the same station, at the same pump, facing the same direction

... and test it several times, not just once


0h well, bet fewer than 10% do all of the above.

I kept a log for every vacation for over 15 yrs when I first got our Bronco. They usually were 1200 mile trips several times a summer (best fly fishing was in BC) Longest was 6300. They give you a pretty accurate idea when you fill up every other day or so and write the mileage down each time.

 

[navi]

When I drove from LA to Norcal on the 5 in my 69 I could see the fuel needle dropping in real time. I never checked the mpg after that. lol

 

[blubuckaroo]

A few years ago I put our Bronco on a diet, and made a few other changes to improve efficiency and performance as well.

I got rid of the unnecessary steel. Rock rails, heavy bumpers etc. Most of that stuff was for looks anyway.
I swapped out the 10 ply tires on steel rims for 6 ply tires on aluminum wheels. This reduced the rotating weight. (inertia)
I tuned the carb with a wideband air/fuel ratio gauge. The engine had been running way too fat.

Now our car is doesn't just get better fuel mileage, but it's way peppier as well. And the best thing... It doesn't stink anymore.

 

[sprdv1]

I saw the title of this thread and thought.... "Those 2 things don't go together!";D

lol, Now that you say that out loud hahaha

 

[Qumanchew]

That is what I keep saying over and over... and over...

... and test the mileage over several hundred miles, not 50

... and fill up at the same station, at the same pump, facing the same direction

... and test it several times, not just once


0h well, bet fewer than 10% do all of the above.

I kept a log for every vacation for over 15 yrs when I first got our Bronco. They usually were 1200 mile trips several times a summer (best fly fishing was in BC) Longest was 6300. They give you a pretty accurate idea when you fill up every other day or so and write the mileage down each time.

Haha, yup. First thing I ask when a fuel mileage discussion starts up...How far off is your Speedo. Average response...oh, I think it's pretty close. Hard to have a serious discussion after that.

 

[Johnnyb]

I think every Suburban lies about the gas mileage those pigs get! You ask them and they'll claim 17 to 20 but you know they're getting 10 to 12.

I only think gas mileage is important as a means of establishing a baseline. I don't care if it's 6 or 16, but I want to know what it is. And then if somebody else with a very similar EB is getting much better and much worse I want to try and figure it out.
In a few weeks, when mine is back on the road, I think I'll be lucky to pull 12. That'll give me about a 240 mile highway range with a 23 gallon tank.

Sent from my Pixel 4 XL using Tapatalk

 

[Silver dollar]

I too asked about fuel mileage on another eb site and immediately got flamed. A lot of responses about "cool factor" and "who cares about gas mileage ".
The reason I asked about mileage was my bronco at that time was a 73 c4 with shift kit, 351 Windsor, 31x10.50 bfg. 4:11 gears.
Best I could get was 10 mpg.
My prior broncos would get around 15 mpg.
My 70 pure stock 302 with small tires,4:11 gears leaded regular gas and lived at 5000 ft elevation would get 15 mpg.
My 71 stock 302 small tires 3:50 gears, also. Ieaded regular gas low elevation, also around 15 mpg.
I think that the smaller tires make a big difference in mileage. Those large tires are like 4 big flywheels to turn along with the rolling resistance.