Can anyone tell me what the average fuel mileage for a stock 46 flathead was? I'm getting about 10 MPG on a fresh rebuild. I thinks that way too low. Dad can't remember what they got originally, thought this was the best place to find out.

 

Well I thought my 47 ford truck with the flathead was the only one with bad gas mileage.
I havent checked it but I know I cant go very far on 10 gallons of gas!!

yo Bill

 

Properly tuned flathead with a Stromberg 2 barrel should get 14 - 18 at 60 mph. These aren't the most aerodynamic trucks, front end is like a 4 x 6 sheet of plywood and there isn't much slant to the windshield.

 

Thanks for the info and your time. Dad will be glad to hear that improvment is possible. though the answer is still unknown. We will try to retune the carb and see if improvment can be made.

 

I had a 1939 Ford 2 door sedan in 1953 which had been completely gone over by the
previous owner. Dad and I went on a one hundered mile trip with it and had to add 4 gallons to fill it, at 23.9 cents per gallon. Dad died two years later, I like a dummie got
rid of the old Ford for a newer(50) Ford and gas prices just kept going up. Those were
some great cars.

 

Y'all are lucky! My 46 Ford 1 1/2 ton, dump with wooden bed, only gets 6-7 mpg...

 

They get what they get in fuel consumption. All you can do is pull the plugs to see if they are running to lean or to rich. Do a vaccum test to see if its getting between 18 and 23 inches at idle. If you added electronic ignition you should see an increase. A vehicle has to be built for low cunsumption, my 80 Vette with a 300hp 350 3:08 4 speed gets 25mpg on the freeway 18 around town.
We went through all the fuel cunsumption hoopla during the fuel crunch of the 70s. Installing the vacuum gauges and doing the light pedal purssure thing to keep the gauge at the highest reading. Bottom line to get lower cunsumption we went to compact cars and scrapped all the gas guzzlers.
I had a 75 F250 4X4 hiboy that had the 390. It would only get 6 miles to a gallon fully loaded, or totally empty, it didn't care.
A truck is a truck it was built to be a work vehicle not a Honda Civic. So just drive it and when you see all the new trucks that the owner is paying an average of $500.00 a month on. Just think to yourself even though the fuel cunsumption is low how much you are saving. Or go buy yourself a 4 cylinder Ranger. That is my 2 cents happy holidays everyone.

 

I recently took my 46 1/2 ton pickup on an 'economy' run, ie driving real gentle, only just touching the throttle, no overtaking etc. This truck has a 3.5:1 ratio rear end and rolls on 205-16 radial tires. I drove at between 2500-3000 RPM, and acheived a miserable 15 MPG [imperial gallon - a bit more than your gall]. I don't know what it is but my 221 powered 35 sedan with a 3.78 rear driven the same would return 27 MPG!!