Potential fuel mileage for 1947 Frazer

[leorob51]

Hello to all - I'm the new adult on the block! I have a 1948 Manhattan that I'm thinking of putting on the road, so I'm interested in what kind of fuel mileage some of you long-time K-F owners are getting. In an 1947 Floyd Clymer report, he says about 20 MPG on the highway. One of my friends said that with today's gasoline, radial tires and motor oil, the mileage should be a bit better. Are there other tricks such as milling cylinder head, multiple 1-bbls.,split intake and exhaust manifolds? Currently, my car has a 2-bbl. carb. Was that standard or optional for 1948? It also have an overdrive transmission in it. I grew up with my father's Rambler overdrives, so I'm very familiar with the operation of the item. I often wondered about having to kick the throttle all the way down, with the resulting waste of gas, just to get back into third direct, so when I installed an overdrive into my full-size 1964 Ford (sorry about the "swearing"), I located a NO switch on the dashboard so when I was going uphill and the engine started to lug down, I pushed the switch and I was immediately back into third direct. You can do the same with any car. Thanks for your club!

[joefrazer]

The setup you have in your car is best for fuel mileage. The two 1-bbl intake actually uses more fuel. With OD, your car at 60mph should deliver a bit better than 20 mpg. I have a 50 Traveler with the 1-bbl carb and OD and I see around 25 mpg on the open road.

Of course, all of the usual applies here...having clean plugs, a good cap, rotor and set of plug wires will help as well.

[Fid]

Hello and welcome!  I had a '48 Frazer standard with a 1 bbl carb and overdrive. I drove it through the late 70s and early 80s and always got 20+ MPG with it.  Some '48 Frazer Manhattans had the 2 bbl carb and I believe a little higher compression head which added about 12-15 HP to  the engine. Yes, that was optional. I'm not sure what that did to mileage but I'm guessing what you're hearing is pretty accurate based on what I had seen with my '48. 
Regarding the overdrive kick down switch - yes, it can be mounted anywhere so you don't have to floor the throttle to kick the car out of OD. We had a '48 Kaiser Custom which we moved the kick down switch under the dash so it could be pressed with your finger.
I don't know if this helps the fuel consumption but it certainly saves your throttle linkage and does not make the engine work at maximum for the 1 second or so it takes to kick it down. I also did this on my '52 Henry Vagabond but then I turned into a bit of purist and mounted the switch back where it was originally. Anyway, I thought it was a bit strange that when the motor is working hard and needs to be relieved that the first thing you do is floor it, making it work even harder for those few  seconds, to get it out of overdrive. I always thought that was somewhat ironic but that's how it always worked.

[rguinn1947]

Hi:
    I own an early 47 Frazer with the 1bbl carb and factory overdrive.  I have tried to keep everything as Henry built it. It gets 20-22 mpg with a high of 23-24 on the interstate (staying about 50-55mph.)  With the 20 gal fuel tank, that is a pretty good range.  Incidently, I am fortunate to have 3 non ethanol gas stations within a 5 mile radius.  The car loves the 91 octane fuel and I don't have to worry as much about the ethanol problems.

[kaiserfrazerlibrary]

Be sure to join the KFOCI.  You get a cd called KFOCI HANDBOOK that has all kinds of useful information on your car.

[kaiserfrazerlibrary]

Things are unpacked now at the new place.  I could get at the factory Service Bulletin that compared Kaiser and Frazer MPG numbers with other makes.  The 1948 engines are same as 1947 models in terms of configuration (1 barrel carb, single manifold, etc):

25 MPH - 22 MPG     30 MPH - 21 MPG     40 MPH - 19.5 MPG     50 MPH - 17.5 MPG     60 MPH - 15 MPG     70 MPH - 13.5 MPG

The test car was equipped with the 4.09:1 rear axle, Dana model 41.

Some cars were equipped with the 3.73:1 "economy" rear axle which could boost the numbers shown 10-15%.  Trade off is that the car so equipped might not be as agile on certain hills as one with a 4.09:


Sources:  Service Bulletins 82 & 382 plus comments from Ford Motor Company Engineers back in 2011