Hypermiling: A new hobby for gas savers & environmentali

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Hypermiling: A new hobby for gas savers & environmentali

Post by Elixer » Tue Jan 29, 2008 7:18 pm

I just recently got into a new hobby, and it's as addicting and enjoyable as quieting a computer. It's called hypermiling, and the idea is to change the way in which you drive in order to improve fuel economy. So far I've gotten more than 40mpg out of my 1989 toyota camry, more than 140% of its rated combined EPA mpg rating, and that is the old rating in which cars scored 10-15% higher than the new EPA rating. This is what got me started: http://www.cleanmpg.com/forums/showthread.php?t=1510
It's a lot to take in at first, but I know a lot of SPCRers are into reducing their power and ECO computing, so I'm sure a lot you would be interesting in using less gas too. What do you guys think of this?

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Post by NeilBlanchard » Tue Jan 29, 2008 7:37 pm

Hello,

I have dome many of these things, and I have had reasonable success: my Scion Xa is rated 32 City 38 Highway, and I have hit a peak of 42.5mpg, and a average over almost 3 years of 37mpg. Which include starting out with a brand-new engine, and (almost) three winters.

I have increased my tire pressure and I coast a lot. The problem I have experienced with higher tire pressure (~40-42PSI) is that traction is reduced, especially in wet conditions and in turns. The recommended pressure is just 32PSI, while the sidewall max is 44PSI. For me in my car here in New England, I have found ~38-39PSI is optimal -- you get noticeably better rolling, w/o giving up traction and safety.

The Xa is challenged in two ways: fifth gear is way too low for highway speeds: the engine runs at ~3300RPM at 65mph. It would be great at 1000RPM less. The second limitation is aerodynamics -- the rear bumper cover hangs down about 6" and I'm sure it catches the air pretty strongly. :(
Last edited by NeilBlanchard on Fri Feb 01, 2008 9:43 am, edited 1 time in total.

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Post by derekva » Tue Jan 29, 2008 10:23 pm

Better yet, lobby your congressional representatives to vote for higher EPA requirements and encourage auto manufacturers to build / import high-mileage diesels. Personally, I'm waiting with bated breath for either a BMW 123d or 323d to arrive in the states.

-D

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Post by hawkeye1 » Wed Jan 30, 2008 1:09 am

derekva wrote:Better yet, lobby your congressional representatives to vote for higher EPA requirements and encourage auto manufacturers to build / import high-mileage diesels. Personally, I'm waiting with bated breath for either a BMW 123d or 323d to arrive in the states.

-D
Or better yet, lobby your congressional reps to authorize drilling in remote areas of Alaska no one will ever see (aren't we drilling in Alaska now, by the way?) and offshore where the Chinese and other countries are (or plan) to do so. Or, even build new nuclear or clean coal plants that in turn will decrease the need for fossil fuels and decrease the need/price of the oil we use. Heck, I'm even in favor of alternative energy solutions, so long as it doesn't involve ethanol which is causing higher food costs, especially damaging to those on limited incomes (already proven, wouldn't we all agree?), and with limited environmental payback.

Listen, the solution isn't to coast our cars or (dangerously) over-inflate our tires. America's known reserves include 60-plus years of oil, 100-plus years of natural gas. And, I stress proven. Let's, as a nation (U.S., that is), for once agree restrictive policies have caused our dependence on foreign sources of fossil fuels (enriching those who wish to do us harm), raised prices that cause serious hardship to the poor and working classes, and have otherwise sensible adults coasting to fractionally increase their gas mileage. Jeesh!

I apologize in advance to those who have already booked their next vacation to the Arctic National Wildlife Refuge.

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Post by jaganath » Wed Jan 30, 2008 2:05 am

build new nuclear or clean coal plants that in turn will decrease the need for fossil fuels and decrease the need/price of the oil we use.
building coal plants decreases the need for fossil fuels? what are you smoking?

cars do not (currently) run on electricity. building new electrical power plants of whatever variety will not affect the oil price one iota.

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Post by aristide1 » Wed Jan 30, 2008 10:04 am

I determined the speed where my mileage starts to drop off, around 65mpg. I stay below it. My EPA highway estimate was 29 and I routinely average 32mpg.

I also use Mobil 1. Does it work? I think it's worth about 1 extra mpg, and I've been using it for since I reached 10,000 miles. The engine runs like new and has passed 228,000 miles. It's not that much more because you do fewer oil changes, so you save on parts and labor. My V6 has a reputation for building up sludge and the dealer charges $800 for this repair. It's more than pais for itself, and it reduces resources used as well.

Think of every time you stop or slow down and money thrown away. Anticipate lights and drive accordingly. Frankly people waste a lot of gas on the highway tailgating, because they are on the brakes so much. I routinely drive over 80 miles without stepping on the brakes even once. The added bonus is my brakes last almost 100,000 miles as well.

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Post by mr. poopyhead » Wed Jan 30, 2008 11:02 am

aristide1 wrote:Think of every time you stop or slow down and money thrown away. Anticipate lights and drive accordingly. Frankly people waste a lot of gas on the highway tailgating, because they are on the brakes so much. I routinely drive over 80 miles without stepping on the brakes even once. The added bonus is my brakes last almost 100,000 miles as well.
AMEN!!!!! we need more smart drivers on the road...

not only does tailgating waste gas, it causes traffic jams (or at least makes them much worse...) and i don't understand why people feel the need to go barrelling into a red light at 80km/h when they KNOW they'll have to stop...

smart driving usually gets you there as fast as agressive driving... slowing down for red lights means that it might actually be green when you get there, :P

ever since i got my own car (well, i share it with my brother...) i've been extra-conscious about every mL of gas... currently, i'm able to get around 1000km per tank on my '92 diesel jetta... hooray for diesel!!!!
once i learn to use more efficient gearing, i can increase my mileage...

anyone have any tips for being more efficient on a manual transmission?

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Post by floffe » Wed Jan 30, 2008 12:44 pm

mr. poopyhead wrote:anyone have any tips for being more efficient on a manual transmission?
When accelerating, try to go straight from 2nd to 4th or 3rd to 5th, if those are the gears you'll use when you're done accelerating. The elimination of one shifting will make up for the higher rev. And always use as high a gear as is comfortable, 5th from at least 45mph and 4th from ~30.

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Post by walle » Wed Jan 30, 2008 1:19 pm

Go not petrol...but diesel, go not automatic...but manual. Or go extreme, go Chinese…go bicycle.

Added:

Keeping the right tyre pressure saves fuel, keeping the engine in good condition saves fuel, avoiding cold starts saves fuel and driving smoothly saves fuel; just to add a few.

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Post by klankymen » Wed Jan 30, 2008 4:49 pm

Yeah, since I got my golf, I go into fifth gear for city driving (60km/h), which makes for good mileage. Unfortunately I have to stay in fifth when I'm on the autobahn (160km/h). It would be nice to have a sixth gear for that.

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Post by nutball » Thu Jan 31, 2008 12:20 am

I've been trying out different driving styles over the past year or so. The tips above (anticipatory driving, using high gears, smooth acceleration, etc.) all really do have a big effect (perhaps as much as 20% averaged over a tank).

Another tip which wasn't immediately obvious to me was to keep the car in gear (high gear) when decelerating and braking until you almost stall. I had naively presumed that coasting in neutral would use less petrol, but it seems that that's wrong. In neutral the engine management system needs to use fuel to keep the engine going -- if you coast in gear the momentum of the car keeps things turning. This can save a fair bit of fuel in stop-go situations like urban driving.

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Post by mr. poopyhead » Thu Jan 31, 2008 5:48 am

here's a tip: draft big trucks on the highway... the lower drag actually makes a huge difference... might be dangerous though, :P
nutball wrote:Another tip which wasn't immediately obvious to me was to keep the car in gear (high gear) when decelerating and braking until you almost stall. I had naively presumed that coasting in neutral would use less petrol, but it seems that that's wrong. In neutral the engine management system needs to use fuel to keep the engine going -- if you coast in gear the momentum of the car keeps things turning. This can save a fair bit of fuel in stop-go situations like urban driving.
this sounds interesting... anyone else have experience with this?

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Post by klankymen » Thu Jan 31, 2008 6:23 am

mr. poopyhead wrote:here's a tip: draft big trucks on the highway... the lower drag actually makes a huge difference... might be dangerous though, :P
Might be dangerous, but not too bad. bear in mind you can brake MUCH faster than a truck, since they have so much more mass to decelerate. However there is the significant disadvantage of not being able to see the traffic ahead of you, which really annoys me.

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Post by AuraAllan » Thu Jan 31, 2008 6:38 am

mr. poopyhead wrote:here's a tip: draft big trucks on the highway... the lower drag actually makes a huge difference... might be dangerous though, :P
Beware of turbulence. It can get pretty scary when getting up behind a big truck and your car starts to shake violently.

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Post by Cerb » Thu Jan 31, 2008 2:31 pm

aristide1 wrote:Think of every time you stop or slow down and money thrown away. Anticipate lights and drive accordingly. Frankly people waste a lot of gas on the highway tailgating, because they are on the brakes so much. I routinely drive over 80 miles without stepping on the brakes even once. The added bonus is my brakes last almost 100,000 miles as well.
I can agree with the throwing away part, and I coast when I can (I don't need brakes at all for maybe 1/8 of lights). But, how can you time lights without weaving all the time, or having everyone right on your bumper (really great in the case something happens ahead of you)? I don't use most of my brakes for stopping, but for slowing down from people coming onto the road (from a stop), ending up behind someone who's brake-happy (lightly uses brakes at long distances, so you never know what's going on), people turning off without their blinkers (just braking, then turning, without any warning prior to starting to brake), etc..
klankymen wrote:Yeah, since I got my golf, I go into fifth gear for city driving (60km/h), which makes for good mileage. Unfortunately I have to stay in fifth when I'm on the autobahn (160km/h). It would be nice to have a sixth gear for that.
While 160kmph may be a little higher than we get to do in the states, I've often wanted for a higher gear, too. Does it really need double the RPM at 80MPH cruising as 40MPH cruising? No, just that I can mash it and then let up, and it will stay in high gear for ~40 (automatic), but it can't go up but one more ratio. So, starting around 60MPH, I can see the tach just keep on going up...

Being able to city drive in 4th (of 5) was about the only plus of my Neon. Near 40 MPG on gasoline came with its costs, however. I'd have hated to get so much as tapped while in it. Now I've wrecked an old Volvo, and don't think I could feel comfortable in another barely-made car like that.

Now that I look it up, I'm getting about rated mileage highway, and far superior city ('05 PT Cruiser, which I hope not to be driving in a couple weeks).
Last edited by Cerb on Thu Jan 31, 2008 4:13 pm, edited 1 time in total.

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Post by klankymen » Thu Jan 31, 2008 2:50 pm

Cerb wrote:
klankymen wrote:Yeah, since I got my golf, I go into fifth gear for city driving (60km/h), which makes for good mileage. Unfortunately I have to stay in fifth when I'm on the autobahn (160km/h). It would be nice to have a sixth gear for that.
While 160kmph may be a little higher than we get to do in the states, I've often wanted for a higher gear, too. Does it really need double the RPM at 80MPH cruising as 40MPH cruising? No, just that I can mash it and then let up, and it will stay in high gear for ~40 (automatic), but it can't go up but one more ratio. So, starting around 60MPH, I can see the tach just keep on going up...

Being able to city drive in 4th (of 5) was about the only plus of my Neon. Near 40 MPG on gasoline came with its costs, however. I'd have hated to get so much as tapped while in it. Now I've wrecked an old Volvo, and don't think I could feel comfortable in another barely-made car like that.

Now that I look it up, I'm getting about rated mileage highway, and far superior city ('03 PT Cruiser, which I hope not to be driving in a couple weeks).
I used to drive a volvo (old 850 of my parents - really nice car actually, though it looks kinda ghetto), and you feel really safe in those, although it was enormous (which is a good thing when you're buying furniture at ikea lol). The golf is nicely maneuverable, but the gear ratios are real different. In the volvo I had to be going 50 (the speed limit in towns here) to get into third gear, and 80 before I could go fifth gear.

Now I'm in fifth allready starting from 55kmh (which is about what I drive in town).

The fastest I've driven this car is around 190, but reasonably I don't get over 165 or so. Pretty crazy that for one third of the speed I drive I have 4 gears, and for the remaining two thirds there's only one gear.

I guess the Golf is more of a city car, with nice cruising fuel efficiency just above the German speed limit.

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Post by CoolGav » Fri Feb 01, 2008 7:05 am

mr. poopyhead wrote:
nutball wrote:Another tip which wasn't immediately obvious to me was to keep the car in gear (high gear) when decelerating and braking until you almost stall. I had naively presumed that coasting in neutral would use less petrol, but it seems that that's wrong. In neutral the engine management system needs to use fuel to keep the engine going -- if you coast in gear the momentum of the car keeps things turning. This can save a fair bit of fuel in stop-go situations like urban driving.
this sounds interesting... anyone else have experience with this?
Yes, on a modern car don't coast in neutral if you overall want to save fuel. It'll save you more out of stop start driving, by accelerating and then coasting, especially if you're intelligent and coast as much as possible (eg up hills, down hills too)...

I find driving a car with a trip computer set to mpg (or l/100km) helps to encourage you to get it better. Since I've had my current car I'm averaged 58.4mpg (4.84l/100km) of Diesel, and that's with very little motorway driving. It helps that it's a good modern 1.5l turbo-diesel, although it's not a small car (at least for me) with 6 manual gears. I use 4th gear (~1500rpm) for 30mph limits (~50km/h). I have the tyres inflated a few psi above recommended so don't lose traction - in fact I love taking bends quickly! It's all about smooth driving.

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Post by CoolGav » Fri Feb 01, 2008 7:09 am

klankymen wrote:I guess the Golf is more of a city car, with nice cruising fuel efficiency just above the German speed limit.
I call the Golf a family car, the Lupo (now replaced with the bizarre fox), or Ford Ka, Fiat 500/Panda, original Mini (not BMW's), Smart ForTwo are city cars - to me at least!

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Post by kittle » Fri Feb 01, 2008 11:01 am

mr. poopyhead wrote: ever since i got my own car (well, i share it with my brother...) i've been extra-conscious about every mL of gas... currently, i'm able to get around 1000km per tank on my '92 diesel jetta... hooray for diesel!!!!
once i learn to use more efficient gearing, i can increase my mileage...
Long live the deisel jetta!
I had a 1980 model while in college. clueless driver that I was at the time, it still got 40mpg in the city. And I clocked it at 55mpg on a long road trip.

it boggles me why the current gen deisels get half that at best :/

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Post by klankymen » Fri Feb 01, 2008 1:04 pm

I don't know what current gen diesels you're looking at, the VW Lupo gets 80 MPG, and even a big car like the new 105HP bluemotion diesel Jetta gets 50mpg combined.

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I think I missed out on the Red Blooded American gene

Post by Cerb » Sat Feb 02, 2008 10:32 pm

klankymen wrote:I used to drive a volvo (old 850 of my parents - really nice car actually, though it looks kinda ghetto), and you feel really safe in those, although it was enormous (which is a good thing when you're buying furniture at ikea lol). The golf is nicely maneuverable, but the gear ratios are real different. In the volvo I had to be going 50 (the speed limit in towns here) to get into third gear, and 80 before I could go fifth gear.
A newfangled computer thing, maybe? I'm now the owner of a 93 240, with a ZF auto, One of the real nice things, just driving home, was being able to rev and release, and get to 4th (highest, OD) before 40 (64 in your numbers). If it had more, it would just be a matter of adjusting the cable to be able to shift right on up. Uphill is really good for shifting it, because revving up enough won't change speed so much while stuck in 2nd. It doesn't make for the easiest time passing somebody, though.

Then again, over there across the pond, don't you guys have decent amounts of manual cars?

850, enormous...you silly Europeans and your space-saving ways :). Don't you have Excursions and Grand Marquis to compare to? :):):)

If I were in the market for a new car, I would be itching for a TDI, be it Rabbit or Passat. High MPG, high torque, good HP, exceptionally safe, not too small...aside from having to learn to care for a different kind of animal, in terms of engine, what's not to love? You might not get the 100+ MPG of some of the hypermilers with new hybrids, but you wouldn't do too shabbily, and would be used to modern diesel engine care by the time diesel hybrids come out. Or, maybe that'd just be a good excuse, since they aren't so ugly as most hybrids out right now :D.

I wonder how many hypermilers have been pulled over due to a few of their tricks being easy ticketing offenses? Rolling stops come to mind.

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Post by Bluefront » Sun Feb 03, 2008 1:34 am

I've been doing this "hypermiling" thing longer than anyone here, I guess.....mostly because I'm cheap, and never liked pouring my salary into the gas tank.

Some cars are better suited to the technique than others. (Of course you should start out with a hi-milege car to begin with) A manual transmission car is the best, but have become a thing of the past in the USA. Having had much bad experience with diesels (I have worked on cars for a living all my life), I refuse to own another diesel, no matter what. So I now drive a small/cheap auto-trans Nissan Sentra.

After I got it, I spent months calculating gas mileage at different speeds, taking different routes to work (most of my driving), and other things. I always run higher air pressures than recommended. Getting the right tires can eliminate most of the adverse effects of doing this.....I use Michelin.

I almost always drive with the windows up.....in the summer the AC is always on. This gives me better gas mileage. The better airflow over the car, more than makes up for the compressor drag. Plus the car is quieter. Did you know truck drivers in the USA have hearing problems with their left ear? Driving with the window down does it.

Coasting helps somewhat, even with an automatic. Shifting to neutral going down long hills saves gas, but is hard on the brakes. I always shift to neutral at long stops......helps mileage, and the transmission.

Removing excess weight from your car can help. I never carry any un-needed stuff in the trunk. And I always remove my rear seats (no kids). Saves weight, and gives more carrying room.

There are some other ways to save gas..... a mod chip in your ECU could do it, but most chips are made for performance gains, not fuel saving.

Federal gas mileage/emission laws have helped the over-all mileage of US cars......but other stupid federal laws have not. Mandated air bags increase the weight, as do the increased weight necessary to pass crash tests. The American public's increased demand for electronic play-toys don't help matters. Massive watt audio systems with big heavy speakers are a major problem with gas mileage.....the drag on the alternator is terrible. I once worked on a car that just had a $4k audio system installed. Every time he turned the thing on and cranked up the volume, the car died......the stock alternator (stupid) couldn't handle the load.

Probably buying the right car to begin with is your best, but most expensive bet for good mileage. But too bad....I'm keeping my $100 used Sentra, rather than buying a $25k Prius.

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Re: I think I missed out on the Red Blooded American gene

Post by klankymen » Sun Feb 03, 2008 3:47 am

Cerb wrote:
klankymen wrote:I used to drive a volvo (old 850 of my parents - really nice car actually, though it looks kinda ghetto), and you feel really safe in those, although it was enormous (which is a good thing when you're buying furniture at ikea lol). The golf is nicely maneuverable, but the gear ratios are real different. In the volvo I had to be going 50 (the speed limit in towns here) to get into third gear, and 80 before I could go fifth gear.
A newfangled computer thing, maybe? I'm now the owner of a 93 240, with a ZF auto, One of the real nice things, just driving home, was being able to rev and release, and get to 4th (highest, OD) before 40 (64 in your numbers). If it had more, it would just be a matter of adjusting the cable to be able to shift right on up. Uphill is really good for shifting it, because revving up enough won't change speed so much while stuck in 2nd. It doesn't make for the easiest time passing somebody, though.

Then again, over there across the pond, don't you guys have decent amounts of manual cars?

850, enormous...you silly Europeans and your space-saving ways :). Don't you have Excursions and Grand Marquis to compare to? :):):)

If I were in the market for a new car, I would be itching for a TDI, be it Rabbit or Passat. High MPG, high torque, good HP, exceptionally safe, not too small...aside from having to learn to care for a different kind of animal, in terms of engine, what's not to love? You might not get the 100+ MPG of some of the hypermilers with new hybrids, but you wouldn't do too shabbily, and would be used to modern diesel engine care by the time diesel hybrids come out. Or, maybe that'd just be a good excuse, since they aren't so ugly as most hybrids out right now :D.

I wonder how many hypermilers have been pulled over due to a few of their tricks being easy ticketing offenses? Rolling stops come to mind.
No, I'm actually referring to a manual transmission. (not many autos here in germany, correct). But I liked to drive the volvo at 2k rpm and above, and you didn't hit 2k until 80kmh. But the golf can be driven at 1.6k, which is 55kmh in fifth.

I was also looking at the TDI Golf (Rabbit to you over-the-ponders), but the mileage savings were not too big with a small 100bhp car, also diesels cost more tax here. the problem with the tdi is, you have to hit 1.5krpm or so before the turbo kicks in, so especially with a small motor, it's a slow start on a hill.

By big car, I mean the biggest I've driven, so I don't have too much for reference. We don't get any of the American SUVs here, the ones that all end with the letters "-er", and sound really funny if you add the word "Anal" in front of them.
However there are a good amount of German SUVs here (X5s, ML-classes and Audi Q7s). And of course many VW vans, which are hardly a small car.
However despite the reduced passenger room in the golf, I like the shortness of it for maneuverability. The total length is not much more than the wheelbase, so no big overhangs there.

Still, if I get more money I'd still like to upgrade to a bigger car, like the new Audi A4, or maybe a previous gen volvo.

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Post by jaganath » Sun Feb 03, 2008 6:40 am

I almost always drive with the windows up.....in the summer the AC is always on. This gives me better gas mileage. The better airflow over the car, more than makes up for the compressor drag.
iirc this is only true at highway speeds, say at less than ~25pmh it's more economical to roll the windows down.
Massive watt audio systems with big heavy speakers are a major problem with gas mileage.....the drag on the alternator is terrible. I once worked on a car that just had a $4k audio system installed. Every time he turned the thing on and cranked up the volume, the car died......the stock alternator (stupid) couldn't handle the load.
LOL, if only that would happen to all the idiots with bowel-looseningly loud sound systems.

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Post by klankymen » Sun Feb 03, 2008 6:55 am

jaganath wrote:
I almost always drive with the windows up.....in the summer the AC is always on. This gives me better gas mileage. The better airflow over the car, more than makes up for the compressor drag.
iirc this is only true at highway speeds, say at less than ~25pmh it's more economical to roll the windows down.
Massive watt audio systems with big heavy speakers are a major problem with gas mileage.....the drag on the alternator is terrible. I once worked on a car that just had a $4k audio system installed. Every time he turned the thing on and cranked up the volume, the car died......the stock alternator (stupid) couldn't handle the load.
LOL, if only that would happen to all the idiots with bowel-looseningly loud sound systems.
lol, you mean that their car dies or that they die?

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Post by jaganath » Sun Feb 03, 2008 7:52 am

lol, you mean that their car dies or that they die?
their car! I'm not some Islamic fundamentalist or something (notice how fundamentalist contains the word 'mental'? :) ).

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Post by djkest » Sun Feb 03, 2008 7:54 am

kittle wrote: Long live the deisel jetta!
I had a 1980 model while in college. clueless driver that I was at the time, it still got 40mpg in the city. And I clocked it at 55mpg on a long road trip.

it boggles me why the current gen deisels get half that at best :/
Why? They weigh more w/ all the safety features and comfort items. Then again, my brother gets 50mpg in his diesel Jetta.

The new deisel regulations helped VW decide to pull the diesel vehicles in the US in 2007. Yay gubmint making things worse not better.
Last edited by djkest on Sun Feb 03, 2008 7:58 am, edited 1 time in total.

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Post by djkest » Sun Feb 03, 2008 7:57 am

In our 2005 Corolla, we just got back from a little road trip. 1st tank of gas, we got 37.6 MPG. Next one was 35.5 MPG driving 80 mph on the freeway in the fast lane. This was with 4 adults and a full trunk. Highest was 41.2 MPG on the same trip, but car unloaded and it was a little warmer outside. I just switched to full synthetic oil, and I'd like to experiment with a little higher tire pressures. Can't pump them too high right now since it's winter.
Last edited by djkest on Thu Feb 14, 2008 6:52 am, edited 1 time in total.

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Location: Buffalo, NY

Post by Brian » Tue Feb 12, 2008 11:45 am

My shifting habits focus on keeping revs low. I found some technical literature on my engine, including a plot of brake specific fuel consumption (BSFC, or grams of fuel per horsepower) as a function of engine speed and torque.

When accelerating, I work my way through all of the gears, upshifting around 2500 RPM. I open the throttle fairly wide, which reduces pumping losses across the throttle and reduces BSFC. My car is equipped with a wide-open-throttle switch, so if I put the pedal to the metal, fuel economy goes down the tubes.

When approaching a red light, I coast down to 1500 RPM, then put it in neutral, braking if needed. Above 1500RPM, with no throttle displacement, the engine uses zero fuel. Below 1500RPM, my engine attempts to idle. Thus, remaining in gear below 1500RPM uses fuel and propels the car forward.

Coasting down to 1500RPM uses the vehicle's forward momentum to turn the engine. If I want to retain my vehicle's momentum, I put it in neutral. Revs fall to 500RPM, where idling uses very little fuel.

Above 1500 RPM, I put it in gear, take my feet off the pedals, then switch the ignition to 'off' with the engine still spinning. Switching it off and on does not affect acceleration and is not the least bit jerky.

Car: 1996 Subaru Legacy, 2.2L, AWD. 22mpg on winter fuel = ~26 gal burned in January. I'd rather be cycling.

djkest
Posts: 766
Joined: Mon Sep 10, 2007 1:05 pm
Location: Colorado, USA

Post by djkest » Thu Feb 14, 2008 6:50 am

aristide1 wrote: Think of every time you stop or slow down and money thrown away. Anticipate lights and drive accordingly. Frankly people waste a lot of gas on the highway tailgating, because they are on the brakes so much. I routinely drive over 80 miles without stepping on the brakes even once. The added bonus is my brakes last almost 100,000 miles as well.
This may be the first time I completely agree with you!

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