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Not sure if this where to post this... so here goes. A friend suggested by adding 1/3C of acetone to each tank of fuel I would notice a difference in fuel economy.
I was concerned about damaging the fuel line and was told the due to the small amount in the fuel nothing would be harmed.
I've been running my WRX on this for 6 months now and figure I get an extra 100kms / for every 40 liters driving around town. Even more when I hit the highway. Has anyone tried this?
 

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Works for me... Been using it in my '02 WRX for 5+years and now in my '09 STi for almost 2 years. I find that 1 1/2 Oz to 2 Oz works the best... You do have to get the amount right for your car... I found that anything less doesn't really do anything and anything more doesn't help either... I have years and years of MPG info and it does work, I average 1.5 MPG more with the acetone without fail. Every time I try a tank without I loose 1.5 MPG on that tank...
 

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How much is acetone/gallon? I've used toluene before, but only about every six months as a fuel system cleaner.
1 1/2 OZ to 2 OZ per tank for my car, but it's can be different depending on the gas in your area... I average 480 KMs/300Miles per tank. ( when the low light comes on)... That's about 22 MPG average, and that average is for the last 2 years with my STi...
 

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So how much is it per ounce?



I already average 330-340miles/tank.. plus I'm going to be switching to e85 soon, which I doubt would see any benefits. I'm just wondering if it's costing you more money to keep buying acetone all the time.
 

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$23 for a 3.78L can, works out to about 18 cents per Oz. X2 = 36 cents per tank and I get an extra 20 miles per tank out of it so... Is it worth it? I guess so, better than a kick in the pants. :)
 

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$23 for a 3.78L can, works out to about 18 cents per Oz. X2 = 36 cents per tank and I get an extra 20 miles per tank out of it so... Is it worth it? I guess so, better than a kick in the pants. :)
I'd like to know how it changes the amount of fuel you car requires to burn to travel a certain distance? If you car needs 10 gallons to go 200 miles, your car needs 10 gallons to go 200 miles, it seems simple. I don't see how adding something to your fuel changes that without fooling the ECU into running leaner in order to burn less fuel. The way I see it (and I could be wrong) is the injectors are told to open for a set amount of time, depending on various sensor inputs, letting "x" amount of fuel into the combustion chamber. Just because there is an additive in the fuel, the injector is still staying open that set duration and letting "x" amount of fuel in unless you are messing with the sensor data or manually telling the injectors to stay open for a shorter amount of time. Not saying it doesn't work, I just dont see how.
 

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I'd like to know how it changes the amount of fuel you car requires to burn to travel a certain distance? If you car needs 10 gallons to go 200 miles, your car needs 10 gallons to go 200 miles, it seems simple. I don't see how adding something to your fuel changes that without fooling the ECU into running leaner in order to burn less fuel. The way I see it (and I could be wrong) is the injectors are told to open for a set amount of time, depending on various sensor inputs, letting "x" amount of fuel into the combustion chamber. Just because there is an additive in the fuel, the injector is still staying open that set duration and letting "x" amount of fuel in unless you are messing with the sensor data or manually telling the injectors to stay open for a shorter amount of time. Not saying it doesn't work, I just dont see how.
It has to do with the AFR. Gasoline has a different stoichiometeric ratio than say alcohol or toluene. When you mix a bunch of different fuels together like that you change the ratio regardless of what the ECU is looking for. So the 14.7:1 for gasoline the ECU is looking for might now in actuality be 13.8:1 due to the property change of the mixed fuels.The front O2 will adjust the fuel trims to hit 14.7:1 AFR (gasoline). Not a big deal except that we don't have 100% closed loop fueling. In Openloop no O2 sensor feed back is used so you would have to adjust manually the AFR table, if it's even that far off. There is a slight fueling correction that does carry over from closed loop but the ECU makes no "real time" adjustment.
 

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I have no idea how it works other than it's "supposed" to lower the surface tension of the fuel and mix better with the air in the cylinder and thus burn better... All I know is that in a years worth of driving I can get 1,440 miles more for just $26 of acetone per year instead of $341 in gas...

EDIT; Oh, and I did manage 32.7 MPG once, trying to drive as nice as possible... Actually got 443 Miles that tank, probably will never be repeated, as I just can't make myself drive like that for long. :)
 
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