Improve your MPG!!!

[CZLN6]

Howdy All:

Gas hit $2.60 here in Idaho Falls last night. I filled the van about a week ago at $2.45. It got me to thinkin' what to do about getting the most of this precious stuff. I can't do much to the van because of the computer control, but I'm going to drive the Ranchero more and I can do stuff to get more MPG with it. Here's what I came up with.

Start with what you've got,
*Advance the initial setting on your distributor.
*Make sure your carb is as lean as possible, not over-choked, low float level and no leaks.
*Make sure your air filter is not a restriction.
*Duct hot air to the carb intake.
*Make sure your accelerator pump is set as lean as possible.
*High temperature makes mileage. Do everything you can to keep the heat in the engine. Try a higher rated thermostat.

Make sure your-
*vehicle is as light as possible,
*tire pressure is at the maximum recommended PSI,
*brakes are not dragging and alignment is dead on.

A taller rear tire will give you a better economy ratio, but you won’t notice in MPG because your odometer won't show the change.

*Next oil change, try a lighter grade of oil. Synthetic oils make more mileage, but are twice the price. They also hold up better in high heat conditions. Do not overfill your crankcase with oil.

Do not overfill your gas tank and don’t be tempted to top it off. These two practices lead to spills, expansion and evaporation. Park in a shady spot whenever possible.

Consider installing a vacuum gauge and relearn to drive by using the gauge to maintain the highest vacuum under all circumstances.

*Avoid cold starts, preheat before starting when possible.
*Don’t idle to warm up, just drive slow and low for the 1st seven miles. *Don’t sit and idle EVER!!! Don't go through the drive-thru window. Shut the engine off and go in.
*Avoid traffic and stop-and-go driving.
*Plan your trips and avoid unnecessary driving.
*Slow down and coast whenever possible.
*Drive as if you have a raw egg between your foot and the gas pedal.

Hope this is helpful.

Adios, David

 

[Anonymous]

Wow 2.60 a gallon. ill take 1000 gallon of that,
hit 3.10 over the mountain from ya in Oregon.
So whats the new rules for this spendy GASOLINA

 

[XFlow_Fairlane]

yeah over $3 here. although I found that driving slower on the interstate helps as does messing with your timing. it will make it a little more slugish but helps you pick up 1-2 mpg. also set the idle speed as low as you can safely have it (so it never stalls at random)

 

[Anonymous]

How about sending Alot of that gas Up north. It just hit 6.45 a gallon here in Cape Breton. And for all you in The US thats 5.43 a gallon.

 

[JackFish]

How about sending Alot of that gas Up north. It just hit 6.45 a gallon here in Cape Breton. And for all you in The US thats 5.43 a gallon.

Since I'm closer to Alberta, we're paying just over a dollar per litre for 87oct.
That's about what, $4CDN/gallon? Of course now is that an imperial gallon? :

 

[Asa]

how exactly does ducting hot air to the carb help out?
i've been trying to think it through, but it just isn't working out...

 

[JackFish]

how exactly does ducting hot air to the carb help out?
i've been trying to think it through, but it just isn't working out...

I was wondering that myself?
Better vaporization?
Of course, up here, in about November I will be pulling the cold air intake off the air cleaner because it will be below zero outside for the next five months! :santa;

 

[XFlow_Fairlane]

it helps to atomize the fuel. also the more heat in the intake charge the easier it is to ignite. hotter air is less dense so less fuel is needed also.

 

[Asa]

that atomization was about the only thing i could think of

 

[CZLN6]

Howdy All:

Gas just went to $2.85 a gal last night. I'm suffering.

The point of hot air to the carb is that hot gasoline is more volitile- Meaning it vaporizes better/faster/more completly, making for more efficient combustion. Cold air is more dense- therefore holds more O2, and makes more power if you rejet for it. Hot air is less dense, but mixes with the gas better. Hot air off the engine/exhaust helps a cold engine to warm up more efficiently.

I drilled a couple of 1/2" holes in the bottom of my air cleaner housing, out side of the filter element, directly over the log, fore and aft. If I want the cold air intake to work, I tape off the holes. If I want hot air I remove the heat vent type duct tape and plug the cold air intake.

The same is true for engine heat. A hotter engine is a more efficient engine. If you can run a 195 thermostat all year around it will save a couple of gallons of the precious stuff. Ergo- avoid cold starts. Once an engine has been started in a day plan to do all your driving needs with the vehicle that has already been warmed up.

Also why it might be a good idea to use an engine heater all year around. Even on the hottest 100 degree day your engine has to warm itself another 80 degrees to reach optimum operating temperature.

Caution- Heat must be managed!

Adios, David

 

[wsa111]

I hate to do it but the 7448-350 CFM holley is going back on my car till this fuel situation is resolved.

The 350 carb is really a very nice driving streetable carb.

Since the weather in my area of the country is finally cooling off I will park the Lightning truck & use the mustang for double the fuel miliage & since it is a non air conditioned vehicle the cooler weather will be in my favor.

For you retired military or active duty personnel, I hear the base fuel prices are going to remain at the post hurricane prices, all you need is your ID card to purchase fuel at a much reduced cost if available. William

 

[Anonymous]

wsa111

It didn't stay the same here in Maryland. It is 10 cents cheaper on base than at the cheapest place in town but it's still $3.09 a gallon on base. And the lines are forever I think you burn more than that just going thru the line.

Bob

 

[Asa]

i wonder...
the Jet Hot coating holds the heat in the headers, would non jet hot headers help MPG more? or is that just going overboard...

 

[CZLN6]

Howdy Back All:

Evan- The coated headers still warn up faster than the engine coolant and are still a good source for warm up hot air.

William- The last horse shows in this area are this next weekend. I was planning to install the #4412 once the horse season was done. I think I'll wait awhile and see what happens. I do have an Auotlite 1.21 that's ready to go and a 1.33 that will be rebuilt soon. The idea was to compare all, so I guess the order really doesn't matter. Right now a Holley/Weber is looking good.

It's too bad you can't swap your annular discharge boosters into your #7448. The Aug 05 issue of Car Craft did a side by side dyno comparison of annular boosters to dog leg in a Demon 750. The annular boosters won out in HP and torque 2,200 up to 6,600 rpms with an average hp increase of 11, with the greatest gains coming in the 1,800 to 4,000 rpm range. The peak difference in HP was at 1,800 rpms at 33 hp. Unfortunately fuel consumption went up too. I guess that makes sense since it is making more power.

Gas is still at $2.85 here and seems to be stabilizing. I guess I can be glad I'm not buying gas in Canada.

62 Fairlane170- Advancing the initial timing should make your engine feel more snappy and economical. You're right about setting the idle as low as possible. Someone mentioned replacing or doubling the throttle return spring as they get weak with time and wear. That will help to get a truer, lower idle quicker. Springs are cheaper than gas.

Adios, David

 

[80Stang]

Consider installing a vacuum gauge and relearn to drive by using the gauge to maintain the highest vacuum under all circumstances.

David, great thread you started.

How to relate vacuum, rpm and engines optimum torque range to MPG results? How about need for gear shifts?

For an example

60mph @ 2300 rpm @ 3rd gear (1:1) @ 13-15in/HG
60mph @ 1800 rpm @ 4th gear (OD, 0.73) @ 10-12 in/HG

all values rough but pretty close to reality. Which is more economical? I'd say they are pretty close (at least in my case, engine has equal torque on those rpms). Driving more on 4th will generate more gear shifts (shifts to 3rd in steep uphills if I want to prevent vacuum to drop = PV to open). Shifts will result more use to accelerator pump; bad for MPG.

Driving at rpm range that is not suitable (too low) for the particular engine will lower the vacuum and eventually so low that you'll be driving the PV open, once again ruining the MPG.

Results depend of course on the profile of the road and exact truth does not exist, but we can draw guidelines.

It hit $1.80 per liter here...I'd love to buy a gallon (3.8L) for $3.00 or $3.50. We just had our club's track & drag weekend which resulted in $150 cost in fuel only...grrr...for 30 miles on track and 2 blasts down the strip. Plus 200 miles one way to do it.

 

[finnstanger]

It hit $1.80 per liter here...I'd love to buy a gallon (3.8L) for $3.00 or $3.50. We just had our club's track & drag weekend which resulted in $150 cost in fuel only...grrr...for 30 miles on track and 2 blasts down the strip. Plus 200 miles one way to do it.

With those prices I'm not ashamed to admit that I've been driving with my japanese "rice cup" recent days (for 39 MPG) But don't worry Teppo, most of gas price (75%) goes to the goverment which is capable of taking better care of citizens :roll: That's what I've been told...Am I been fooled again?!

I remember hearing our current Industrial and trade minister criticizing gas taxing policy when he was not in charge.....

 

[addo]

I suppose maximum economy is had at the point of maximum VE.

But that may be an empirical value of economy; it may not relate to practical driving conditions unless we gear very specifically for that situation.

Or am I totally off track?

I remember hearing our current Industrial and trade minister criticizing gas taxing policy when he was not in charge.....

Always the way. It's human nature, I think. Just like how we all make fun of Jessica Simpson but nobody would decline a date with her...

 

[saltwaterfalcon1960]

Regular is $3.30 here in coastal S.C.

 

[DYNOED250]

fuel hit 1.45 AUD per liter today :<:<... this is cray shit... its doubled in just 2 years....

 

[Lazy JW]

Consider installing a vacuum gauge and relearn to drive by using the gauge to maintain the highest vacuum under all circumstances.

David, great thread you started.

How to relate vacuum, rpm and engines optimum torque range to MPG results? How about need for gear shifts?

For an example

60mph @ 2300 rpm @ 3rd gear (1:1) @ 13-15in/HG
60mph @ 1800 rpm @ 4th gear (OD, 0.73) @ 10-12 in/HG

all values rough but pretty close to reality. Which is more economical? I'd say they are pretty close (at least in my case, engine has equal torque on those rpms). Driving more on 4th will generate more gear shifts (shifts to 3rd in steep uphills if I want to prevent vacuum to drop = PV to open). Shifts will result more use to accelerator pump; bad for MPG.

Driving at rpm range that is not suitable (too low) for the particular engine will lower the vacuum and eventually so low that you'll be driving the PV open, once again ruining the MPG.

Results depend of course on the profile of the road and exact truth does not exist, but we can draw guidelines.

It hit $1.80 per liter here...I'd love to buy a gallon (3.8L) for $3.00 or $3.50. We just had our club's track & drag weekend which resulted in $150 cost in fuel only...grrr...for 30 miles on track and 2 blasts down the strip. Plus 200 miles one way to do it.

I am guessing that you already have a tachometer and a vacuum gauge installed, these are very useful in the quest for improved fuel mileage. I believe that an air/fuel ratio meter would also be useful, I intend to install one someday but need to get the pickup running first :roll:

I think, but cannot prove, that the lower the rpm the better the fuel mileage AS LONG AS THE AIR FUEL RATIO REMAINS FAVORABLE! But if the power valve opens and richens up the mixture, you will lose the benefit of higher thermal efficiency that is gained by lugging. Obviously, this is a game of compromises. Good luck!
Joe