I got 34.5 MPG in my 3.0!

[Green Dragon]

I had to make a quick 220ish mile round trip last week to Park City Utah and back for work and decided to do an experiment with pure acetone.

I filled my gas tank with 100% ethanol free gas. 88 octane is the only grade available. My gas tank was about 1/4th full of 10% ethanol 91 octane. I mixed in 4.5 ounces for 24.5 gallons of fuel. (1 ounce per 5 gallons or 1 once to nearly 700 ounces of gasoline. Its a pretty small amount relative to the gas.

I was in a bit of a hurry to make an appointment and got 28.0 mpg getting there and did some city driving while there. Upon leaving I reset one of the mpg calculators and let it go. I was amazed at what I was looking at. Granted there is an elevation drop but does bottom out with some hills and climbs. I had 42 mpg for a while, then dropped to 37.3, climbed to 37.9 in the flats and remained there until I hit a mountain pass in a canyon on my way home to Logan. The final mpg upon returning to the same gas station and topping off was 34.5 mpg! I had consumed 8 gallons over a 242 mile trip total with some city driving which calculated out to 30.25 mpg!

I changed directions several times going east on I-80, west on I-84, north on I-15, and north east on US- 89. There was nothing for wind. I did not draft trucks.
I drove conservatively and egg shelled the throttle. I did drive about 70 give or take 5 mph. Sometimes 80 for sections. I used the A/C to my destination. A/C off returning home. Sun roof open. I am running 17's with worn tires. Haven't checked psi in a while. My disa vane has been removed from the unit in the intake. Going to repair that soon.

I generally do better than average than most report on their mpg, but this is amazing. I'm shocked with some disbelief. The X is peppier as well and runs smooth as it always does.

I know someone is gonna flame me for using acetone..... but if you do, please back up your claim. I am not telling anyone to try this. This is simply my experience. I have been looking into this for a while.

I will post pictures that I cataloged tonight after I get them off my phone to follow the unofficial "pics or it didn't happen" rule.

[PandaTrader]

I dont understand where do you get that gas, from a regular station?

[Green Dragon]

Yeah we have one gas station here in town that sells 88 octane ethanol free. Thats it. I have read that the acetone mixture works best with no ethanol. So I tried it as perscribed. It worked for me.

[PandaTrader]

Originally Posted by Green Dragon

Yeah we have one gas station here in town that sells 88 octane ethanol free. Thats it. I have read that the acetone mixture works best with no ethanol. So I tried it as perscribed. It worked for me.

Crazy. I got a 3.0 as well. So just Look for that 88 octane Ethanol Free gas, and I'm good to go? Is that ok for the engine?

[Green Dragon]

Yeah 88 octane should be fine. 91 octane is what is recommended, however this does not mean you cannot run a lower octane. Your knock sensors adjust for a range. I'd stick with 87 and higher. It reallly depends on the fuel as there are alot of variations in fuel from season to season as well. You kinda need to see what works for you. Its hard to find ethanol free fuel these days. You can google it for your area. There are some gas stations carrying it now for marine and small engines as well as to attract business as there is a demand for ethanol free fuel. 10% ethanol in our fuel generally yields lower gas milage as it contains less energy.

As far as adding acetone to your fuel, do so at your own risk. I am not advocating it. I feel its safe enough to do at small amounts, but that is my opinion. Do some research on your own.

I will be testing it over the next few months for long term observations.

[JCL]

Originally Posted by Green Dragon

I know someone is gonna flame me for using acetone..... but if you do, please back up your claim. I am not telling anyone to try this. This is simply my experience. I have been looking into this for a while.

I won't flame you. But I will point out that the acetone mpg miracle claim has been pretty thoroughly debunked. The results claimed by various promoters have not been independently reproduced, and the scientific basis for the claims of improved mileage (better vaporization of liquid gasoline) are not sound. But glad that you had a good drive. Let us know how it goes over time.

[Green Dragon]

Thanks JCL. I know my experience thus far is inconclusive by any means. I can't explain the extraordinary gas mileage, especially in the mountainous region I'm in. I drive this route every week end during ski season, and have never seen anything close to this. I used ethanol free gas all season till march until my station switched to 10%. Another station started carrying one grade recently. Maybe it cleaned my injectors......who knows. I'll post future results. I have never heard of anyone getting that good of mileage in an e53.

Oh btw... I just bought an 2004 e83 X3 3.0. 6 speed manual with sport, cold, and premium packages. I know you have a newer one with the 3.0si motor. I'm just a little jealous.

It is black with terracotta leather. Its super clean with all service records. I'll post pics in the appropriate forum when I take delivery.

My wife is excited as it will be her car. I am flying across the country to get it tomorrow in Philadelphia region. I'm ever-so-slightly nervous about having two X's in the fold. I've had exceptional luck with my two e53's. Fingers crossed. I will get to know it well during my "little" road trip.

[Green Dragon]

Update: My computer took a dump on itself with my mileage spread sheets with both my X5 and wife's X3. I had these pics on my phone still from my Park City trip, so I figured I'd post these in case my phone dies on me as well. My experiment with acetone is far from done, but have had some good results on a few trips. I've had some variability as expected to different factors. Winter blend fuels don't seem to be that great for mileage btw.

Achieved 26-28 mpg in the X3 coming across country (2000 miles)(loaded down) (NC to Utah) with a few high points of sustained 31-36 mpg. It was tough to maintain non-ethanol fuel blend as it wasn't always available, so my data for that trip was mixed.

On another 500 mile trip to Las Vegas, we were in a hurry to make a flight, and bombed through the desert in the late night (traveling at an undisclosed rate ) Lets just say we did very well for the rate we were traveling......

I have not had or noticed any problems with the small acetone blend running in both vehicles. I think there is something to it, but again my results are inconclusive and far from done. This is simply my experience thus far. I will start a new spread sheet with data logged. I also have a source for 91 octane non-ethanol now.

(Pictures are in chronological order) Theoretical 828 mile range on one tank (at 34.5 mpg or 744 miles at 30.25 mpg) anyone?

[JCL]

Don't believe the OBC, especially if you are changing fuel characteristics, as it is calibrated to gasoline.

Fill the tank and measure miles covered, over several tanks, and report the figures back.

[davintosh]

Originally Posted by JCL

Don't believe the OBC, especially if you are changing fuel characteristics, as it is calibrated to gasoline.

Fill the tank and measure miles covered, over several tanks, and report the figures back.

This is the way to do it, and from your opening post, it looks like you've done that...

Originally Posted by Green Dragon

... I had consumed 8 gallons over a 242 mile trip total with some city driving which calculated out to 30.25 mpg!

30.25 is your actual average, which is still pretty darned good. I suppose you were getting better mileage when running strictly highway, but 4.25 mpg more? I dunno... The best way to determine that is to fill up, hit the road, stop for fuel somewhere down the road, fill up again and divide your miles by gallons. It'd be interesting to see how close your OBC is.