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Warm air intake.
Topic Started: Nov 20 2009, 05:13 PM (1,432 Views)
dept411
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Metro on the brain
[ *  *  * ]
I ran a test last night on removing the air intake snorkel. I ran thermocouple wire directly into the breather. The ambient temp was 48deg. With the car cold the temp never icreased above 45deg while driving around at 45-55mph. With the snorkel removed allowing air from inside the engine compartment
to be drawn in the temp stayed at 55-58deg. I left the snorkel off and will continue to so I can see if mileage increases. If it does I guess I'll be making a box over the exhaust manifold.

Has anyone ever preheated their fuel and seen an increase in mpg? I was thinking that an automatic radiator with the oil cooler inside would be a great place to preheat. How hot could it be before you started having problems? Thanks.
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mwebb
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FOG

..."
Has anyone ever preheated their fuel and seen an increase in mpg? I was thinking that an automatic radiator with the oil cooler inside would be a great place to preheat. How hot could it be before you started having problems? "...


bad idea
the return line will return much / most of the fuel to the fuel tank so you will be heating the fuel in the fuel tank as well .....
which will make the fuel evaporate and tax or overwhelm the limits of the evap system in the car
which will vent fuel vapor to atmosphere
vented vapor will not be combusted in your engine

thus , fraking up your fuel economy .....

the OE fuel system suppliers have been using returnless fuel systems for sometime now to prevent that very thing from happening
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dept411
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Metro on the brain
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I thought the pump dead headed at the throttle body and kept a constant pressure. It recirculates the fuel to the tank? There must be some type of pressure regulator in line past the throttle body? Man I have alot to learn about these cars. Thanks
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mwebb
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FOG

a quick way to see if you have sufficient fuel flow volume is to remove the return line and check for fuel ...
if yes
there is more than enough fuel flow volume

to run the engine
assuming the fuel pressure regulator is not stuck open
which is very rare


and the pressure regulator is returning what fuel is not needed to the fuel tank...
.......................

there is probably a "too warm value" on the WAI as well , i have no idea what it may be
for the record
my snorkel is in the hatchback area as well .... about 4% FE improvement at 37f
in the one test i did so far
i can measure intake Air temp with scan data .... but
it's on the list ...
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dept411
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Metro on the brain
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I think my fuel sys is ok. I was just looking to improve mpg. I am only getting 42mpg right now and would really like to get that number up. So far all I ahve done is a good tune up ,headlight covers and remove the snorkel. I would like to lower it and block off the front a little. I also would like to install led lights all the way round.
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nerys
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Grr

well you COULD cool the fuel down again on its way back too so you don't run into the evap problem. would not be too hard maybe even run it through say an oil cooler or something but in miniature say a little radiator like used on water cooled computers?

what kind of gains might heated fuel get you assuming you could control the evap problem?
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Manny
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Yes! a Costa Rican member

Actually the pressure regulator is located inside the trottle body, showing up it's diaphragm:


Posted Image
By mperaza at 2009-11-20
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dept411
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Metro on the brain
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Good idea nerys! I have heard someone say that they wrapped copper tubing around their lower radiator hose to heat the incoming fuel. I guess you could do the same coming back out of the throttle body just try and get some air flow on it to cool it down.
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nerys
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Grr

it would be a fairly easy mod if the fuel lines are accessible but what kind of gains might one see from heated fuel? in the winter you might not need to do anything with it being so cold. ie just being in the stock lines going back might be enough to cool the fuel.

ie would the gains be measurable?
Edited by nerys, Nov 21 2009, 02:10 AM.
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dept411
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Metro on the brain
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I went out and took a quick look on my break trying to find the lines. I couldn't make out which ones were which. I'll check at home in my manual. This might be a fairly easy modification to do with the right fittings.
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Woodie
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In the excellent picture above the fuel lines are at four and six o'clock, they have yellow paint on them. I think the one on the bottom is supply and the one on the right is return, but I might have that exactly backwards. Wrapping copper line around a heater hose would be easier as the heater and fuel lines are already pretty close to each other. Also, the heater hoses always have hot water in them, on a very cold day the lower radiator hose could be quite cold.
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dept411
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Metro on the brain
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Got out today after I woke up and found them. I'm not sure which one is the pressure line. They are on the right side of the throttle body one comes in from the front the other from the r/side. They are close to the upper rad hose and it looks as if all I need is some hose/clamps/copper tubing and insulating wrap. I'm finishing up on 12hr shifts right now at work and with an hour drive each way I dont have much time for tinkering. I might try and start something Monday and post some pics.
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billy508
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billy508

Just something to think about. In 1971 my cousin Dickie Davis won the Snowball race here in Pensacola. He did it by going all the way on one tank of fuel. It was just 200 laps back then. He did it buy packing his gas in dry ice for over 24 hours. They filled it with the cold fuel right at the last min. He is a note where they accuse him of having too big a fuel tank.. :evillol :evillol ...............................................The 1973 Snowball Derby race was filled with charges of cheating. Davis' victory was protested because he went the full 200 laps without pitting for fuel. But officials checked his tank and found it to be the required 22-gallon size, upholding his victory. Before the race, officials said the engine in the car of polesitter Pete Hamilton had been moved forward overnight and made his crew put the engine farther back. He finished well back in the field :banana :banana :banana ps I really dont know how many know how he did it. But now you do also :news
Edited by billy508, Nov 21 2009, 06:56 PM.
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mwebb
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FOG

so then
it would seem that purchasing your fuel on a "cold" day as opposed to a "hot" day
would mean
there would be more fuel per dollar in your tank
as
fuel is measured by volume and not density or weight or mass .

of course the fuel storage tanks are under ground where temperature is a constant ....
but if a station just got a delivery
on a very cold day
or any day where ambient temperature is below about 50f
the ambient temperature may have some effect on the fuel while it is in the tanker truck
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billy508
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billy508

Copied from a trade site :thumb For over 30 years, temperature compensation has been discussed and debated in the weights and measures community. NIST has been in the middle of the discussion, providing technical advice and information as evidenced by the 1979 publication of our report: “Symposium on Temperature Compensated Volumes in the Sale of Petroleum Products.”

So what is temperature compensation? Temperature compensation as it relates to the sale of petroleum is an adjustment made that assures that each gallon of fuel sold contains the same energy content. To put it simply, energy per unit of fuel is measured at 60 degrees Fahrenheit and when the external temperature is warmer it causes the fuel to expand. A warm gallon of gas does not provide as much energy as a cold one. That is because when that cold gallon of gas is warmed, its volume expands. To compensate for this phenomenon, weights and measures officials may rely on formulas or mechanical means to compensate for temperature differences. States may choose their preferred implementation. With automatic temperature compensation, the measuring device on an application adjusts the volume indicated for any delivery to a reference temperature. For petroleum products, the reference temperature is 60 degrees Fahrenheit – which was established in the 1920s by the then National Bureau of Standards and American Petroleum Institute. Some states specify that a gallon of gasoline is defined as 231 cubic inches at 60 degrees. The state of Hawaii has adopted an alternate reference temperature of 80 degrees Fahrenheit for petroleum. Because of Hawaii’s tropical climate, the temperature of gasoline will not vary by more than a few degrees. The rest of the states have more variable climates, so the 60 degree reference makes more sense for the
In some states, compensating for the temperature of refined petroleum products being sold has taken place at the wholesale level -- but not at the retail gas pump (diesel included) or for deliveries of home heating fuel. Some states prohibit temperature compensation at retail and some states prohibit temperature compensation anywhere in the petroleum distribution chain. Most states require temperature compensation for certain products, such as for liquefied petroleum gas (LPG) sales, or propane for home heating, but not necessarily for other products. :drivin :drivin :drivin From what I have read Canada has pumps that compensate for the temperature difference.
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