Improving Gas Mileage

[Old Henry]

I haven't had any better than 11 mpg since my 59A-B was totally rebuilt on my '47 fordor but have heard others get much better. I'm thinking that it is most likely the high altitudes I run at (5,000 - 15,000 feet elevation). Would that increase or decrease the gas mileage? I run the sea level size jets on the 94 to reduce ping. That would use a little more gas too. I run timing fully advanced for the high altitude without any ping. Don't know what else could be done. I'm open to any ideas.

I'd probably put my money into an overdrive if I really cared.

[51 MERC-CT]

Riunning sea-level jets at altitude equals rich mixture.

[41ford1]

So what size jets are you running? I'm currently running #51s. I am fairly close to sea level. You might experiment with #49s. If they don't induce a ping, then try #47s. The effort will be trial and error to find what works. The only real way to check mixture is with a AFR meter. That requires installing an O2 sensor in the exhaust system.

[ken ct]

Originally Posted by Old Henry

I haven't had any better than 11 mpg since my 59A-B was totally rebuilt on my '47 fordor but have heard others get much better. I'm thinking that it is most likely the high altitudes I run at (5,000 - 15,000 feet elevation). Would that increase or decrease the gas mileage? I run the sea level size jets on the 94 to reduce ping. That would use a little more gas too. I run timing fully advanced for the high altitude without any ping. Don't know what else could be done. I'm open to any ideas.

I'd probably put my money into an overdrive if I really cared.

Henry,i would try a pr of .049 MJ and mayby even a pr of .048 if still running rich and take plug readings on both sets. OMO Also use a 5.5 Power valve in it. ken ct. I have anything you would need.

[ken ct]

Originally Posted by Old Henry

I haven't had any better than 11 mpg since my 59A-B was totally rebuilt on my '47 fordor but have heard others get much better. I'm thinking that it is most likely the high altitudes I run at (5,000 - 15,000 feet elevation). Would that increase or decrease the gas mileage? I run the sea level size jets on the 94 to reduce ping. That would use a little more gas too. I run timing fully advanced for the high altitude without any ping. Don't know what else could be done. I'm open to any ideas.

I'd probably put my money into an overdrive if I really cared.

Probebly run you about $50 for everything including shipping. 2 prs of jets ,powervalve and gasket set.

[Brendan]

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Old Hennery, my mileage in my 36 pickup around town is about 9 mpg, on back roads I have gotten 15 mpg I have a 411 rear with 6:50 in the rear. one other thing is I put on a different air cleaner with a K and N air filter. when I first put on the new air filter I could hear the motor breath I think it made a big difference

[Ol' Ron]

Yes you have to lean it out at high alt. your best bet is it start leaning it out or run an AF meter also you don't have enough advance in an 11A dist. 49's would be a good start.

[larry/Texas]

Brendan, what is the part number of the K&N air filter element you used and what air cleaner did you use. I am trying to improve the breathing of a 21 stud engine with inserts.

Thanks for your help

[flatjack9]

If you are getting some ping, that would sound like you are pretty well maxed out on advance. What octane fuel are you using? Is the vacuum brake working? Also, you could try a colder spark plug.

[Lawson Cox]

Best way to improve YOUR gas mileage is to lie about it, like everybody else does. LOL

[bobH]

I've kept mileage records on all my cars, forever. My experience pretty much supports what you are seeing, and also, what Lawson is saying. (I'm at 6000 ft, with a lot of 'up-and-down-the-hill' driving, and down the hill at about 1000-1500 ft.)
'Course, the other comments are spot-on, too, regarding tuning. Gotta lean it, if you want to tune for altitude. But then, if you drive 'off-the-hill', like I do, then the mixture is too lean. For me, I run 'stock', for down the hill, and eat it on mileage, for up the hill. Lawson offers the best approach for improved mileage. Heck, I got 22 once, and 27 another time.

[1937pickup]

I agree with bobh-that is what the mileage is for these old cars-there is a reason we pumped all the oil out of east Texas.

[David J]

I brought the old Ford photo thread up and this pic is from page 24 - post 478 . Anyone have info on the results of this ? Not gonna get into the mileage discussion but 11 MPG !!!!!!! . Adding another pic from the same thread . Seems mileage can be found . Ditto on the real gas thing as I just made several major gathering trips to OK & other places with my new pickup and the gas in OK was non-ethanol and it got noticeably better mileage then . Non ethanol gas is all over here in WI also .Might wanna try it like suggested above .

[Lawrie]

Hook up an Air fuel ratio meter and then you can get the mixture spot on,
VERY easy to do and I would not try and set up a carburetor with out one now.
Lawrie

[Elmo Rodge]

Originally Posted by bobH

I've kept mileage records on all my cars, forever. My experience pretty much supports what you are seeing, and also, what Lawson is saying. (I'm at 6000 ft, with a lot of 'up-and-down-the-hill' driving, and down the hill at about 1000-1500 ft.)
'Course, the other comments are spot-on, too, regarding tuning. Gotta lean it, if you want to tune for altitude. But then, if you drive 'off-the-hill', like I do, then the mixture is too lean. For me, I run 'stock', for down the hill, and eat it on mileage, for up the hill. Lawson offers the best approach for improved mileage. Heck, I got 22 once, and 27 another time.

Bob, I'm gonna guess since you're at 6,000 feet you are no longer in the San Gabriel Valley. Wayno

[Henry/Kokomo]

Per suggestions made by other 'Barners, I used .049" jets in the 94 on my 59ab in my '46 Tudor. I found I had better throttle response than with the .051's that were in the car when I got it. The combination of the smaller main jets, a K&N filter, a rebuilt and adjusted distributor and carefully monitoring tire pressure got me an added 1.5+ MPG. This was in northern Indiana which is flat and at about 1000ft (I think). FWIW

[BUBBAS IGNITION]

Originally Posted by Old Henry

I haven't had any better than 11 mpg since my 59A-B was totally rebuilt on my '47 fordor but have heard others get much better. I'm thinking that it is most likely the high altitudes I run at (5,000 - 15,000 feet elevation). Would that increase or decrease the gas mileage? I run the sea level size jets on the 94 to reduce ping. That would use a little more gas too. I run timing fully advanced for the high altitude without any ping. Don't know what else could be done. I'm open to any ideas.

I'd probably put my money into an overdrive if I really cared.

Your 11A distributor has 11 degrees distributor (22 engine) and the advance slot is another 12 degrees, ie. 6 up and 6 down. That would equal 28 degrees when fully advanced.
I would suggest less timing , Maybe timing slot inthe center , and then retard it some and check timing..
Too much timing would fire btdc and tend to slow the piston down loosing some power especially at cruise speeds etc...causing poor mpg ?
Today's clean emission vehicles run retarded and very lean.
Something else to think about.

Typically we are wanting it to rev up not being concerned about mpg?

[38 coupe]

11 sounds low to me. Are your brakes hanging up? Is your odometer reading accurately? If the odometer shows less than a mile when you actually drive a mile, your mileage will falsely calculate low.

[ford38v8]

Now, I've got to say... Lawson's answer is the most accurate I've heard or read about on any subject, bar none.

[chuck stevens]

Ol' Henry, Try a tank full of real gas if you can find it. Gasoline with NO methanol, around here we go to the boat yards or airports. Try this before changing the jets, I think you'll be surprised, Chuck S.