Saturday, June 23, 2007

Acetone does NOT improve gas mileage...at least not for me!

Not only does acetone not increase your gas mileage, it actually DECREASES gas mileage.

I kept track of the gas mileage for each tank for the past several tanks. Here were the results...

18.9
18.5
16.9
17.9
18.2

Guess which one is the acetone tank? You guessed it. The tank where I got 16.9 mpg. The 17.9 tank was mostly interstate driving, including one part where I thought I was in 5th gear when I was actually in 4th, and set the cruise and drove for about 15 miles with the engine revving over 3000 rpm. In the Jeep, of course, you don't hear engine noise at 70 mph; you only hear the violent rustling of the ragtop.

So, there you have it. Unless there's something I missed or did incorrectly, acetone will only hurt the gas mileage in the Jeep.

Is this scientifically conclusive? Probably not, but with gas at it's current price, I can't afford to find out.

Monday, June 18, 2007

Acetone for gas mileage = utter failure

Well, it didn't work. I've been keeping careful records of my mileage for several weeks now. For the record:

Regular highway driving: 18.5, 18.2
Freeway driving, tires at 35 psi: 17.9
Regular highway driving with acetone: 16.9

There ya have it. More to come.

Thursday, May 24, 2007

Speaking of Jeeps-How to Fix Faded Fender Flares - Cheap

Most Wranglers have plastic fender flares that are a dark shade of gray or black. These things are great when new...they look good and they're durable. But, as they age, they start to fade to a light gray, and even Armor All doesn't bring them back; it seems to evaporate the instant you put it on.

Some people suggest that you paint the fender flares. That will work, but it opens up a whole new can of worms. You have to prep the things so the paint will stick, and they're likely to be oily from protectant applied in the past. Also, there's the issue of either removing the flares for painting, or masking, which is a scary proposition...how do you know you've got all the little gaps sealed so there's no overspray? You don't, until you remove the tape.

There's a cheap, effective, and safe method for temporarily restoring your fender flares to their original appearance, if you're willing to do a little work and spend a few bucks.

First, you need to get some Black Magic Tire Wet. I've been able to find this fairly cheap at most dollar stores, but if you can't, you can get it here.

The stuff is thick and oily and smells like cherries. If what you get isn't like this, then you don't have the right stuff.

The trick to getting this to work is the application. If you just rub it on with a cloth, it will fade rather quickly and leave the fenders light gray again. Instead, get a 3" paintbrush and a small container, like a styrofoam cup.

Pour some of the Tire Wet into the cup and start brushing it liberally on your fender flares. Seriously, put it on as thick as you can, until it almost drips off the fender flares. Don't be stingy with your love. When you've got them completely covered, leave them alone and go inside and have a drink or something. When you come back, they will look splotchy and drippy, with wet and dry spots. This is normal.

Next, brush over the flares with your brush, but do NOT apply more Tire Wet. Spread out what's on there. Now, give it another 10 minutes or so, and spread it again, without applying more. Keep doing this cycle of spreading then letting it stand, spreading and letting it stand, until it remains even and uniform after you've spread it out.

By that time, your fender flares should be very dark, possibly darker than they were new, and look like this:
They will also be extremely glossy. If you don't like the glossy look, wait about 24 hours to allow the Tire Wet to soak in completely and rub them out with a cloth. This will give them a more satiny sheen, more closely approximating how they looked when they were new.

Reapplying the Tire Wet every two weeks or when you notice fading will keep them looking like new. And, if they've already been treated using this method, it will be easier to reapply the next time.

TJ Acetone Gas Mileage Experiment - Day Three.

No real news to report. I've driven over 50 miles now with the gasoline/acetone mixture in my tank, and the Jeep seems to be purring along fine. I haven't noticed anything quantifiable as far as differences, but the engine does seem to run a bit smoother, especially on acceleration. Not more powerful; it just seems like the engine isn't working as hard to do it's job.

This is not measurable, I realize, and it's entirely possible that I'm dreaming the whole thing. I wish I'd have done some measuring before I started experimenting. I'd like to see if there was any difference in idle speed, acceleration, etc. so I could have some immediate results.

As it is now, I'll have to wait until the next fill-up, which could be a while, especially if the experiment goes well.

Wednesday, May 23, 2007

98 Jeep TJ - Gas Mileage Experiments - Testing Acetone.

If you own one of these things, then you know why I'm talking about this. Mine is a '98 2.5 liter. It has all the features...no power, loud noise, and my personal favorite, bad gas mileage. You'd think a four-cylinder would be fuel efficient. You'd also be wrong.

To be fair, this engine has over 80,000 miles on it and has been completely bulletproof. If the gas mileage were better, I could live with the lack of power...I could rationalize it as a tradeoff.

I can't do much about the power, or lack of it, but I have had some minor success in the gas mileage department. The thing about Jeeps is that they remind you of the importance of good aerodynamic design. Every mile in a Jeep is a rolling battle with the molecules of air that don't wanna get out of the way. And instead of coaxing them gently to the side, the Jeep rams its way through like a rabid bull.

That makes it hard for the TJ to maintain speed going up steep hills on the freeways. It also makes the gas mileage take a nosedive.

So, for over a month now, I've been avoiding the freeway on the trip to work. Fortunately for me, I was able to find a route that takes just about the same amount of time as the freeway trip.

I used to get roughly 230 miles out of 13-14 gallons of gas. That's roughly 16-17 miles per gallon. When I cut out freeways, my gas mileage improved to between 18.3 and 18.9 MPG, and my distance per tankful increased to 250 miles or more. Not much, but it's a start.

Something else I plan on trying...I'm going to inflate my tires to 38 psi to reduce rolling resistance. Also, take Jeep's advice and follow the horrible, annoying shift light. Hopefully those will make a difference, too.

Another thing that I am trying is somewhat controversial. It is said that adding 2-3 oz of acetone to every 10 gallons of fuel will result in a gas mileage increase. I've read all over the internet about people doing this and achieving significant mileage gains. I've also read about Mythbusters trying this unsuccessfully. I've ALSO read that Mythbusters did not conduct the experiment correctly, and that yes, by Golly, it really does work! So, since there's so much contradictory information about it, I decided to try it myself.

The story is, you're supposed to use 100% pure acetone, and that decreases the surface tension of the gasoline, allowing it to vaporize more completely, yielding more power per piston stroke. At my local drugstore, "pure" was labeled as "professional" quality fingernail polish remover, consisting of "100% Acetone". It was about $4 for a 16 oz. bottle. According to my tank size, that should be enough to treat 3 tankfuls of gas. That's about $1.30 extra per tank, at least for me. It will be interesting to see, should there be any benefit, if it will be great enough to offset the extra cost.

Yesterday, I filled the tank and put in the acetone. Today, I drove it for the first significant amount of time, on the way to work. I didn't notice much, except for one thing...it took longer for the engine to come up to full operating temperature. About 3-5 minutes longer. And, at first, when the thermostat would cycle on and off, the temperature would drop significantly, according to the temp gauge. Usually, with most late 90's Jeeps, the temp doesn't stray far from 210 degrees, but it was coming down considerably during thermostat cycles. By the end of my commute, the temp gauge was firmly at 210, like always, but it took longer to get there, because the engine wasn't generating as much heat. And everyone knows...a well cooled engine is an efficient engine, right?

Time will tell if this makes any difference. My gut says no, but I figured, for $4, what's the harm in trying?