Gas Mileage down? - Spring is coming
 

Just entered by second tank in the database and was looking at those with the top mileage....and those at the bottom. Real clear (and no suprise) that the top several cars were driven in temps around 60-70, :shade: while the lowest several list temps in the 20-30 range :cool:.

So...for those in the north, keep the faith, as spring is on the way...even if the thermometer outside is telling a diffrent story!;)

Re: Gas Mileage down? - Spring is coming
 

16F this morning. Bleh.

I guess I should be happy I can maintain 45+ mpg with underinflated tires and winter gas in sub-20F weather. http://wap.srb.co.yu/forum/images/sm...n_rolleyes.gif

Re: Gas Mileage down? - Spring is coming
 

Why don't you guys just all move to the beach in Southern California?
We have lots of affordable housing and no traffic congestion at all.


Hahahahaha

Re: Gas Mileage down? - Spring is coming
 

I've 'hypermiled' (51-52 mpg) the last couple of tanks at 25F with some really sticky ice tires (Michelin X-Ice), so I'm really looking forward to seeing what I can do with summer tires and warmer temps.

BTW, is there an 'optimum' operating temperature for the HCH? I'm hoping yes (but I think probably not) - that way I can catch up to the leaders while they're blasting their AC in 'suboptimal' heat :)

Re: Gas Mileage down? - Spring is coming
 

Optimal temp would be the same temp as the engine block heats up to so none of its heat is lost to the atmosphere.

Unfortunately that would be very very hot, probably way over 300 degrees F.

In practice hotter is better, unless the humans turn on the air conditioner or open the windows which will increase drag.

Frankly, when it is very hot I recommend driving naked and carry a spray bottle of water to cool yourself down.
You will get great MPG.:shade:

Re: Gas Mileage down? - Spring is coming
 

Yeah, I knew that - 'hope' just got the better of me :(

Re: Gas Mileage down? - Spring is coming
 

I haven't updated my tanks in a while out of laziness but will hopefully find the time to do so soon.
For my commutes this winter have been 30-low 40's at night and 40's to 60's day. I've been driving all freeway and been averaging around 55-56MPG. The few FAS's I get have saved me from the low 50's.

Re: Gas Mileage down? - Spring is coming
 

Also keep in mind, when it is colder out it will take your car longer to warm up. It will take longer for the ecu to have it's engine temp/battery charge variables met. So you won't be getting your autostop as soon in that cold weather either.

The problem with warmer weather is that your intake charge temp will go up, which isn't the best way to make the most efficient power. This is why you generally see a lot of the aftermarket intakes for car labeled "cold air intake" which usually means that they pull air from a cooler spot than the engine bay (usually the fender well or grill).

Re: Gas Mileage down? - Spring is coming
 

That's how you get the GREAT MPG:)

And by drawing such attention, you are promoting the Hybrid.:P

We should ALL be so dedicated to our causes.

Re: Gas Mileage down? - Spring is coming
 

My last tank was aweful. Something like 42mpg. Cold temperatures were only part of it. I filled it up too early, so I didn't get those last 150 miles, with a low fuel load. I also, my wife had to drive it for 50 of the 350 miles, and killed the mileage.

Re: Gas Mileage down? - Spring is coming
 

w00t!

Today was my first ever morning commute that my trip MPG ended up higher than when I started. Yay for for starting your car at 27F instead of 10F! :P :D

Re: Gas Mileage down? - Spring is coming
 

The weathers helping me too, after several 25-26mpg tanks this current tank is way up from there. Scangauge is at 28.5 for the tank so far and my daily average for today was 31.5. Should be getting into the 30 all summer long.:shade:

Re: Gas Mileage down? - Spring is coming
 

And to think I complain when I'm driving in 30deg instead of 40...

Re: Gas Mileage down? - Spring is coming
 

Yeah, I'm *so* looking forward to that - at least we've gone from -10F last week up to 15F this week.

I've been logging my morning commutes, and it looks like about a 2 mpg change for every 10F - anybody else have data like that?

Re: Gas Mileage down? - Spring is coming
 

All of you northern tier drivers have my undying sympathy. I just did 494 mile on 7.688 gallons to get 64+ mpg for a tank. Sorry about bragging but I am elated and can't help myself. The temp soared to 85 here in Dallas for a couple of days and I reaped the benefits. I did get 52.5 the tank before ( 40-50 degrees) and am looking at 61.2 mfd this tank (220 miles). So hang tough. Your mpg will improve dramatically once it warms up in a few weeks.

Re: Gas Mileage down? - Spring is coming
 

This is contrary to better fuel economy. Warm weather is better. With warm-air intake, the gasoline more readily vaporizes, and you get more complete combustion, and less waste = higher fuel economy.

Maybe cold air intake is good for street rods and superchargers, and when getting the very last horsepower at terrible MPG matters to you, but its NOT good for Hybrids!!!
:P

Re: Gas Mileage down? - Spring is coming
 

Hybrid performance is a more complex than just the engine:
- cold air is dense thus increasing energy demands at higher speeds
- cold lubricants are viscus thus increasing energy spent moving the parts
- cold manifolds, engine blocks and catalytic converters require warm-up
- cold batteries need to be warmed up to operating temperature range

As for less efficient, gas only vehicles, they have energy to burn. In fact, that is their problem . . . they burn too much energy. The cold weather effects are less noticable as they are shelter behind their existing inefficiencies.

Bob Wilson

Re: Gas Mileage down? - Spring is coming
 

cold air is good for one thing only with respect to combustion engines- higher density...more oxygen per charge, nature's little turbocharger, in effect. But more oxygen requires more fuel to remain stoichiometric... lower FE.

Other than that, is saps efficiency everywhere, as bwilson pointed out. Additionally, the greater temp difference between outside and the engine block means exponentially more energy lost through the block walls instead of being put to useful work.

Re: Gas Mileage down? - Spring is coming
 

This morning wasn't too good. 18F. Meh. Doesn't matter. I finally ordered a trailer hitch and a bike rack for my car last night. Should have everything ready for the weekend (fingers crossed). I'm going to try to fit in a ride or two. I need to get outside and exercise. I need that more than higher MPG right now :)

Re: Gas Mileage down? - Spring is coming
 

Any chance we're getting a break-in advantage due to the cold? Maybe a 'subzero cylinder hone' or a better bearing break-in that might lead to easier rolling during warm weather?

Just dreaming - anyway, it's almost over for this year, and next year I won't care, really I won't...

Re: Gas Mileage down? - Spring is coming
 

Finally, warmer weather!

It's amazing how direct a corolary effect there is, looking at my tanks it seems pretty clear. Temps went up to the fifties, and just one commute in the warmer weather (Up a whopping 20 degrees from earlier this week), tank average shot up 2.6 MPGs just like that.

Re: Gas Mileage down? - Spring is coming
 

Re: Gas Mileage down? - Spring is coming
 

I am LOVING this hot spell- my mileage shot up to new personal bests and I don't even think I was driving differently! On one leg of my commute (22 miles) the average went up from 48.0 to 53.3! Oh, if only it weren't about to drop thirty degrees today.... These great numbers won't even last the whole tank! But really, the things I'm hearing- 81 degrees in DC in mid-March? That's just so ridiculous! Still, I'm anxious for summer now, because if this is a preview of the gas mileage that's possible with a little more skill in warm weather, this is going to be a good year.

Re: Gas Mileage down? - Spring is coming
 

Our warm spell ends today. Rest of the week will be mid 30's for highs. Meh.

Re: Gas Mileage down? - Spring is coming
 

The cold weather can be discouraging, but then I ask myself - What would you be getting if you weren't driving a hybrid? The answer to that is even scarier than watching the FE drop.

Re: Gas Mileage down? - Spring is coming
 

The weather seems to be unsure, that's for certain. 70's, 20's, 50's in three consecutive days. I'm looking forward to the warm and some better MPGs.

Re: Gas Mileage down? - Spring is coming
 

Well, not to dominate the topic, but we seem to finally have some signs of spring, with temps this week being in the 60's, and touching 70 today, and boy does it show! Monday morning, 31.4. End of driving Wednesday, 34.1.

Re: Gas Mileage down? - Spring is coming
 

Yes! I just scored my first 50+ tank. http://www.forumeye.it/invision/html...ons/woohoo.gif

I would've done better but the beginning of the tank had about 4-5 days of 45 MPG driving due to cold mornings. From the last couple trips I think there's a 60 MPG tank in there somewhere. I may not be able to coax it out just yet but I will be sorely disappointed if I don't get at least 53-55 MPG on this tank (starting today).

Gas is now $2.66. OPEC punks http://users.telenet.be/eforum/emoticons4u/mad/1018.gif

Re: Gas Mileage down? - Spring is coming
 

Congratulations, Sledge!! That's fantastic! I know you can hit 53-55 if you try.

If the weather stays nice for a few days, I think I may get 50 or 51 from this tank, which is my goal at the moment. Today is such a beautiful spring day that I feel good to be alive, and I'm sure that my car can feel it, too, and wants to respond by giving me the best mileage it can. (well, maybe I'm just projecting). This seems to be the perfect interval- not hot enough to think about air conditioning, but the engine doesn't need to warm up and I'm not running the heater. Go for it!

Re: Gas Mileage down? - Spring is coming
 

I had posted on another site yesterday that I had a new record - 62.2mpg for my 20.8mi commute in to work (41F, no wind, 30-55mph, all on secondary highways). So...spring is (almost) here. :shade:


Congrats to everyone who's seen better / record trips / tanks in the last few days. There's even better ahead, if you persevere :angel:

Re: Gas Mileage down? - Spring is coming
 

LOL, my goal for the summer? Reach 35 for a tank average.

Filled up today, 400 Miles, 36 MPGs. Guess I'll have to shoot for 40 as my summer goal, like Gary said I should.

Re: Gas Mileage down? - Spring is coming
 

Meh. The last week has been cold mornings and lots of windy afternoons. Doesn't look like I'll be getting 55 MPG for this tank. Looks more like low 50's. Again I say meh :(

Re: Gas Mileage down? - Spring is coming
 

Low 50s is nothing to say meh about, even if you were hoping for better things. Don't be too disappointed! Just reflect that the people who should be saying meh are the other drivers on the road who aren't doing half as well as you are.

I'm hovering around 50 myself despite hoping for a bit better numbers on this tank, but the chill and wind you're getting in Michigan must be coming right across Lake Michigan from Chicago, because it's been iffy here.

I wonder if night driving makes much difference to FE? I often leave work very late and make the second half of my commute well after dark, when the heat of the day is over and it's colder than it would be. Not as much traffic or stop-and-go, but cooler temperatures- it might even out. By summer I'll probably be glad of it.

Re: Gas Mileage down? - Spring is coming
 

Would you prefer I say "Ni!"? :D:D

http://i2.tinypic.com/t0kgma.jpg

Re: Gas Mileage down? - Spring is coming
 

Somewhat.

At the FEH Experience, they discussed the effects of headlights and cooler temperatures. Both eat away slightly at your FE, though if your commute is long enough, the cooler temperatures can be counteracted by the longer trip.

Re: Gas Mileage down? - Spring is coming
 

Being in Houston, I've haven't been looking forward to spring, especially with a pregnant wife and 90% humidity. I've had to use the A/C a lot, and I'm averaging 41 mpg so far on this tank. I guess only six more months till fall, right?:cry:

Jeff

Re: Gas Mileage down? - Spring is coming
 

Sledge: you can say meh if you want, or Beans! as my grandmother would exclaim. :) I was mostly trying to cheer you up. But you seem pretty cheerful, so I won't worry about it. Summer is on the way!

Pravus Prime: Good point about the headlights. They do use some energy, but not as much as the AC or the fan. More than the radio, you think? My commute is 22 miles door to door, so low temperature isn't AS big of a problem, but it's not nothing. I can't wait for hot weather and sunny days and sandals, grass and flowers, buds and new leaves. It's all going to be so much more enjoyable in a nice quiet HCH or with the engine off at a stoplight, listening to the songbirds in the sky. :)

Re: Gas Mileage down? - Spring is coming
 

As I said, we got a breakdown at the FEH Experience. (This is for the FEH, naturally, the HCH will vary.)

Radio .1 MPG
Rear Defrost .8 MPG
Headlights .9 MPG
Fan on High 1.3 MPG

The AC at low speeds can be as much as 20% lower FE, while at 65 and above aaround 10% drain.

Re: Gas Mileage down? - Spring is coming
 

Woo-hoo, 37.1 MPG, a new personal best!

I'm loving this warm!

I know nobody cares, but...
 

39.3mpg and 482mi when I filled up this afternoon! And what a nice day it is :shade: