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How did you do it?? MPG bragging rights!!


Farmall Cub
Lately I've been getting 10 mpg on the highway, and 14-16 on the streets (minimal stop lights, like 4 in town). I don't know why but my mpg randomly dropped again after I fixed it. :[

and does anyone else get better mileage going 35-40 rather than 50-55 like i do?


Farmall Cub
Lately I've been getting 10 mpg on the highway, and 14-16 on the streets (minimal stop lights, like 4 in town). I don't know why but my mpg randomly dropped again after I fixed it. :[

and does anyone else get better mileage going 35-40 rather than 50-55 like i do?

At least on my truck, 34-40 is the lower end of third gear, so that's where the milage is best.


Farmall Cub
Ah. 35 -40 is the low end of my 4th gear. I'd like a different axle ratio. 373's are great and all....

Hal Steward

Farmall Cub
Hell of a truck motor?
Did you put it in an actual truck?
Sorry but I remember my uncle putting a Ponitac v-8 into a F-6 Ford about 1963-64 to replace the flathead. He ran it for awhile but put the flathead back in since it outperformed the Pontiac engine on 1/2 or less HP in that application. The car motor had no low end torque.

Yes it was in 1100b 4x4 rhoades lifters headers Something may have been wrong with that Pontiac But I was geared down some But don't get me wrong I still respect and admire the Ford flat head They are coolest with more after market stuff still today Offy heads and twin dueces sweet and they will hold there own still

Bill Bennett

High Wheeler
There was one time long ago (real gasoline days), I filled both tanks early in the morning before driving the Travelall out to Mojavy, CA. Gas mileage was nearly 23 mpg. As we drove from the rather cold and foggy costal area up to the much warmer desert area, the gas started expanding to the point I had overflow conditions from 'both' tanks at the same time! For a while, the gas was expanding faster than the engine was using it! Of course, coming back down from the desert to the cooler areas, the gas 'shrunk', which didn't make me as happy! Highway mileage now with the Ethanol added is closer to 14+ mpg if I keep the vacuum guage above 15 and the speed below 65 mph.
Bill Bennett 68 Travelall 1100 4X4 304A 2300 350 cfm

derik martin

Farmall Cub
My 1975 Scout with 3.07 gears, stock 304 and stock tire size gets a solid 14-16mpg highway at 70-75mph.

My 1974 200 pickup with 3:73 gears, 32 inch tires and 392ci motor with headers gets no better than 9-10 MPG going 65-70 and it get's much worse in town.

Most of my driving is I-8 east from San Diego where it goes from Sea Level to a little over 4,000 feet.

My 2008 Toyota FJ Cruiser gets about the same mileage as the scout and must downshift on every long hill, both IH vehicle climb everything with no shifing or even slowing down.


Farmall Cub
Back in the late '70's we were operating a fleet of conventional school buses on Loadstar chassis. Most had SV345's and 5-speed directs. Most were geared to go 55 MPH @ 3000 RPM's.

We used one bus for a test bed to find out what worked the best for fuel economy.

Some of the parts and pieces we used included a Mallory MSD iginition and a Holley 2300 Economaster carb.

On route we were able to consistently get 8-9 MPG, up from a consistent. 6-7 MPG. It doesn't sound like a big improvement, but in a fleet a 25% increase in fuel economy can make a big difference in the fuel bill.

Today, my '65 1200C T-all with SV304/4-speed/4.09 gears consistently gets 14-15 MPG on the highway. It is pretty much bone stock. It prefers to cruise at 55-60 MPH so I stay in the grandma lane.

I would imagine that massaging the carb, updating the ignition, and some sort of OD gearing could improve the fuel economy all the way up to 18 MPG on the highway. Or repowering to a 7.3L or 5.9L may improve things up to 20-22 MPG.

The question then becomes is the cost of improvement and bragging rights worth the cost of time and $$$.

As far as I am concerned, it runs well enough right now. I think I will spend my time and $$$ on something else.


Farmall Cub
Like most, I get about 8-10 around town and 10-14 on the highway. 2BBl 304, 31x10.5R15, fiberglass rear quarters. T-18.

The earlier comments on the vacuum gauge, on my 1992 Audi S4, which is a turbo, I have a Boost/Vac gauge and when gas prices were high I watched that thing like a hawk and stayed off boost. That car I typically average 19MPG, but got up to 24MPG driving like a little old lady in a buick. :D

I have some more work to do on the Scout this Winter and unless I were to go EFI or get a DUI (no not the drinking kind) I doubt there is any extra MPG in my future. It is acceptable however. There is a reason they stopped making them in 1980.

Brian Tucker

Farmall Cub
Over the Holiday's I drove my 72 scout with 345, Automatic, fuel injection, and 2.72 gears from Bennett, CO to Claremore, OK. The first leg of the trip with wind was coming from the East at 15 to 25 mph. I was driving fast and average 73 mph for the complete trip. The speed limit in Colorado is 75 mph and was holding that speed throughout most of the trip. I was using a GPS to check my mileage. I averaged 13 mpg.

On the return trip home I averaged 62 mph. I drove from Chickasha, OK to Colby, KS and never exceeded 65 mph. I did fall below 60 a few times but averaged close to the 62 mph mark. I averaged 16 mpg (404 miles to 25 gallons). There was zero wind north on I-35 from Chickasha to Salina, KS. Once I began heading west the wind was from the northwest about 10 to 15 mph.

Truck has dual exhaust with headers. 235/75/15 tires. 62 mph crusing RPM was 2,000 to 2,100. The motor is not new. 33 gallon tank.

Ty M

Farmall Cub
Again not a Scout but I got nearly 20MPG out of my '98 GMC pickup one time and I wasn't driving like a granny. I just kept my foot steady on the pedal.

I find that consistency with your foot is what makes for good mileage. Your speed will fluctuate if you hit a hill but it'll come back when you crest it and descend. I got 18MPG in the same GMC during holiday weekend traffic (I-95 towards DC, anyone?) and then later that night in the rain, I had a 700 pound 304 engine in the bed of the truck, still on the same tank of gas. This time I was driving pretty slowly as was the speed of traffic.

If you don't stop and go in traffic on the interstate it helps a lot, too. Just pick a speed that's about average (if you're going 0-25MPH and then braking back to 0, 10-12MPH would work) and keep your vehicle at that. It saves wear on the brakes/clutch, saves stress, and saves a tremendous amount of fuel. You just have to learn to suppress that feeling that the car in front of you is beating you to your destination. :boat: