trends in gaslogs, come discuss...

[Project84]

Here's what I notice. I notice those of you getting 50+ mpg, have similar trends in the gaslogs, where in the "notes" section, I've even seen 30mpg averages and then someone will write "began hypermiling" and the average for that tank will be like 38mpg.

Or I'll see baseline tanks and notes like "pre-hypermiling" with averages in the 30's and then an upward trend to the 50's.

How is it that one day you people just "decided" to start hypermiling and the gas mileage goes through the roof? I'm not calling you liars, but damn, I have seen TINY improvements thus far and I've drastically altered my driving habit (although my car is inheritly not a gas saver (dohc + automatic)).

My scangauge is on the way, will I be happier when it shows up?

Also, my mileage is generally about 70% city and 30% highway. I only drive 6miles to/from work each day, barely enough to let the car warm up.

I haven't done any mods really other than strict maintenance and 50psi in tires. Saturn owners please chime in!

[dosco]

Originally Posted by Project84

Here's what I notice. I notice those of you getting 50+ mpg, have similar trends in the gaslogs, where in the "notes" section, I've even seen 30mpg averages and then someone will write "began hypermiling" and the average for that tank will be like 38mpg.

Or I'll see baseline tanks and notes like "pre-hypermiling" with averages in the 30's and then an upward trend to the 50's.

How is it that one day you people just "decided" to start hypermiling and the gas mileage goes through the roof? I'm not calling you liars, but damn, I have seen TINY improvements thus far and I've drastically altered my driving habit (although my car is inheritly not a gas saver (dohc + automatic)).

My scangauge is on the way, will I be happier when it shows up?

Also, my mileage is generally about 70% city and 30% highway. I only drive 6miles to/from work each day, barely enough to let the car warm up.

I haven't done any mods really other than strict maintenance and 50psi in tires. Saturn owners please chime in!

Look at my log. You will note that the highway drives get way better MPG using hypermiling techniques than city.

I was able to get 42 mpg on a long highway drive - I was shell-shocked. Using the same techniques on my commute to work (mixed highway and city), I get about 32.

Without any hard data, my super-simplistic explanation is that the fuel flow rate is largely the same for any given RPM...so in slower city traffic (i.e. lower gears) for a given fuel flow rate you get lower mileage. That same flow rate at highway speeds nets you a much better MPG number.

[GasSavers_BEEF]

I think partly the difference is that it takes a lot of faith, guts and to be honest, a huge pair to cut your engine off for engine off coasting (EOC) the first time you do it. once you see that it won't hurt your vehicle and will yield better mileage, you find more and more places to do it.

I am not recommending that you do it but that is what I have found. think about it. if you take your last tank and add 10, 20, or 30 gas free miles to the tank (because that is essentially what EOCing is doing for you) then yes your mileage will shoot through the roof.

also the scangauge will help out a lot because you can instantaneously see when you are using a lot of gas and when not.

*edit* I am not saying not to EOC, I am saying to make sure that it won't hurt your vehicle first, knowledge is power.

[Project84]

I EOC when possible, but on my daily commute, there just isn't much possibility for it. 6 miles, all of which the car isn't even warm yet, so if I try EOC it just dumps fuel on startup, and, my car is an auto, so EOC isn't as easy as just clutch starting from a roll.

I EOC'd on a few highway commutes on my first 30mpg tank as seen and read in my gaslog, but I can only roll about 3 miles at any given EOC spot, as here in hilly KY, once you're rolling down the hill, its not long before you're climbing another.

What are more techniques I should incorporate?? I realize the WAI will help a lot, and I've been putting off fabbing one until I got a scangauge so I can monitor air intake temps... same is true for grill blocking. After those two mods, what's left?

[kamesama980]

it also depends on the car and what the baseline numbers are as to how radical the change is. 35-50 mpg is what? 30% gain? now what's a 30% gain on a 20 mpg baseline? 6 mpg. it's not just the peak mpg but how much they've improved it. look at my truck, I've been very unscientific about changing things around (just add them in whenever) so it's been a very gradual increase and it started low but still over 25% (gas log average is lowered by the history... boo)

basically, you don't have to wake up and decide one day to hypermile. just gradually do it more and more. it has the same results even if it does take longer

[Hateful]

For me; I started logging here after a couple months of a different Hypermiling site, but political differences cause me to leave that one. Once I had my ScanGauge I drove some just to test my techniques for a couple tanks, but now just drive when I actually need to go somewhere. I kept experimenting with Aero mods as the winter weather set in, so it was like paddling up stream. I didn't lie, but my cars nose still kept growing.

[101mpg]

Many of us kept gaslogs before starting here, which is why you see pre-hypermiling in the notest for some, and for others they have tried out a few things first that helped before taking the plunge to things like EOC. This may be a couple of the reasons you see this.

Some only track highway miles, as their city driving can be measured in full tanks and so can their highway.

Some of this is placebo and self-fulfilling prophesy too. When one gets a scangauge they are usually happier (I hope you are too) and they also can start fixing the worst driving habits - so the addition of a scangauge will nearly instantaneously help them fix their bad driving.

When you start posting your gaslogs chances are you start to watch them more closely too, so you drive more carefully. Basically the more you try to save mileage, the better you will get at it, and it will keep increasing. The more you show it to the public, the better you'll want your numbers to be, sort of "keeping up with the Joneses" but on the internet scale.

Plus you'll feel more relaxed with saving money & fuel, so you will not need to hurry so much, meaning you'll start keeping speed down - all of these things will coalesce for you and you'll have a LOT better mileage!

[theholycow]

Take a look at my logs. Mine have gone up steadily like yours.

I suspect that for your 6 mile commute won't be able to gain much -- and I doubt that WAI and grill blocking can help in such a short ride. You might need some crazy mods to get it to warm up for your commute, or a block/oil pre-heater system that lets you warm it up on mains power before you start the engine.

Really, though, you aren't putting on many miles so your gas budget is pretty small regardless of how many MPG you get.

[bowtieguy]

quick response...

let's assume a 40% increase over pre-hypermiling.

20% increase via driving tech is reasonable, then figure another 20% via SEVERAL other mods.

any combo of overinflated tires, grill block, synthetic fluids, EOC, weight reduction, tune-up/fuel cleaner, aero mods, etc could TOGETHER be significant.

[opelgt73]

Originally Posted by Project84

How is it that one day you people just "decided" to start hypermiling and the gas mileage goes through the roof? I'm not calling you liars, but damn, I have seen TINY improvements thus far and I've drastically altered my driving habit (although my car is inheritly not a gas saver (dohc + automatic)).

I've been keeping track of my mileage since I was 16. I never used any hypermiling techniques until recently.

With some cars you can get better results than others. I generally average 28 with my 6cly BMW which is much higher than EPA but no matter what I do I can't seem to average any higher than that unless it is a road trip where there is 99% highway. Then I might be able to hit 30mpg.

On the other hand I was averaging 16mpg in my SUV mixed and just by driving the speed limit and avoiding jack rabbit starts I get 18mpg consistently in mixed driving. It's no fluke either, I consistently get 18mpg tank after tank after tank. I think with a little bit of weight reduction and a grill block I could easily push past 20mpg.

I gotta tell you though, I looked at your gaslog and thats pretty abysmal. I easily average higher than that and my car is a 6cly. You either have something seriously wrong with your drive train or you need to make a more radical change in your driving habits.