This post has been edited by Raptorguy: Mar 19 2008, 10:28 AM

"One of the most important tips is to fill up when your gas tank is HALF FULL or HALF EMPTY."

Wow...whoever wrote that is retarded.

Here's the scoop on that story:

http://www.snopes.com/inboxer/household/gastips.asp

snopes.com and urbanlegends.about.com are good places to check stuff out, especially the many stories of people giving away money or sick kids.

The first one is true though. I always fill in the morning, and when I'm around 1/4 tank.

A few other tips:
Every few months, put some fuel system cleaner into your tank to keep it clean.
Make sure your oil is clean, less friction = less heat = lower fuel consumtion.
Inflate tires.

My question is how much of a difference would that actually make? I mean, I just get gas when I need it, and I try to do it as quick as possible. You're spending money either way.

I feel the same way. If anything you're maybe saving mere cents...

If you care that much that you're willing to spend half the day pumping gas, just do yourself a favour and buy a golf cart

This post has been edited by ListerStorm: Mar 28 2008, 02:30 PM

Try reducing the cars weight by modifications to the chasis or frame of the car, or, you could get different parts for the vehicle to make it more efficient in performance, while using less power.

I should know, I own a 1995 3000GT VR4 Twin Turbo that was literally a 2.5 ton beast and after modding the engine and swapping out parts for more efficient ones while not making any significant changes, I remodeled the car to have the year 2000 conversion, and the car is just under half its weight
and I'm, getting between 50-55 mpg with around 450 hp.

That'd be a good, but costly alternative, but it pays on the long run.

Oh yeah, uh huh, I believe it :

This post has been edited by Spitfire: Jul 5 2008, 01:38 AM

The morning thing is bs. Fuel pumps measure out fuel and compensate for density changes. The only thing about fueling in the morning is that they usually change gas prices later in the day, usually around morning rush hour. Fuel pumps compensate for change in temp, density, etc.

I cant say for the octane boosters/fuel cleaners. Changing your oil regularly will help a lil with mpg. Less dirty and less older oil is more efficient as far as rotating parts and less friction is more efficiency. Tires are the same as well. It's always good to check your tire pressure once every week to 1 1/2 weeks. If you're under inflated you've got more tire on the road than normal and more friction, thus lowering your overall efficiency. Dont overinflate your tires though, that is unsafe and could result in an accident.

The biggest way to save money on gas? Dont drive like a douchebag. Go the speed limit, use cruise control, slow down early and dont try to brake as late as possible, coast when possible, e.t.c. If you do smart driving you'll save gas. My new Nissan Versa is only supposed to get 31-32 mpg. By driving smart I usually get 34-36 mpg.

It's also said that every 5 mph over 60 you lose X% of efficiency. Also goes for every 100 lbs. Whats that mean? Clean the junk out of your car or lose some weight fatty! Dont try to blast the A/C either. Just get let your car air out a lil before turning it on so the A/C doesnt have to work as hard and once it gets to a comfortable temp, turn it down and dont use it as heavily.

Basically, being smart about driving habits will save you more than any weird method. Also, half the "gas saver" things like the Tornado thing you stick in your intake dont do jack. Popular Mechanics tested all of them and none really got over a 1% increase in efficiency.



rrrrrrrrrrrrrrrrrrrrrrrrrright.

This post has been edited by Zadkiel: Jul 5 2008, 07:42 AM

That's the other problem with fuel efficency... as cars become more and more complex, more power is needed to run all the opeartions... take the Mistubishi 3000GT for example. When it debuted in '92 the VR-4 was the most advanced car on the road. Mostly because of its 4-wheel-steering system. And the all-wheel-drive... and the massive 6-cylinder, twin-turbo engine... and the luxurious interior... and sunroof... all adds up to a lot of weight. So I suppose you replaced the body with a carbon-fiber tub, ripped out the interior save for one, maybe two carbon-fiber seats covered in a millimeter of alcontara, stripped out the A/C, the heater, the radio, replaced the wheels, replaced the glass with plastic, replaced the 4-wheel-steering and all-wheel-drive chassis for rear-wheel-drive... that sound right? About a $200,000 job to slash 1750lbs out of that car? That's cool I guess... so your 2000lbs, 450bhp car, that does what, about 220mph and 0-60 in 3.2 seconds?

You could put that engine in a Lotus Elise, and it still wouldn't get 55mpg

This post has been edited by ListerStorm: Jul 5 2008, 11:35 AM

Weight is the enemy of efficiencybut, with the NHTSA standards going up, automakers are forced to make stiffer, more impact reistant chassis and have 5000 safety measures now-a-days. my 1990 240SX has 0 airbags while my new 08 Versa has 6....STANDARD.

Yeah, any engine pushing over 300-325 hp isnt going to get over 40 mpg. Maybe if it weighs 1000lbs and is an I-4, but we cant afford Ariel Atoms(I think the Atom 3 gets somewhere over 34 mpg or something)

As for the speed limit, I don't follow it. The speed limits around here would make it impossible to get to work on time. (most of the speed limits around here are lower than 40, retarded for a 6-lane highway)

But when I used to drive the speed limit (20-40) as opposed to now (35-55 [60 if someone ahead of me is going even faster]), I've haven't noticed anything in fuel economy.

But going too fast does hurt mileage, alot. I have a story to go with how I know this.

Another thing that might help is changing parts. Gearing, suspension, and exhaust are a few.

Well, I've got a few practical driving tips to increase your MPG. I'm repeating some of what others have said, and correcting some other stuff. Hey, it's okay, there's so many popular opinions out there that it's hard to know what's right these days.

As for the "every 5 mph over 60 loses you 5% mpg" and stuff like that... well, obviously you burn more gas when you drive faster in a given gear, because the engine's spinning faster But what most people don't realize is that an engine's fuel consumption is exponential with RPM. I know people who'd tell me that an engine at 2000 RPM consumes fuel twice as fast as one at 1000 RPM.

Wikipedia Article on fuel injection, explains flow rates at different RPM

For those of you who don't click the link, an example 5.0L V8 at maximum power (assumed 5500 rpm) consumes 68 times as much fuel per unit time as it does it idle (assumed 700 rpm). So really, driving 65 instead of 60 will hurt mileage, but driving 70, or 80, etc. will hurt it exponentially more, not in X% increments per X mph. So on the highway, where most people I know speed to some extent, try not to speed TOO much and you won't do too badly.

In town, all that starting and stopping kills fuel economy - we all know that much. And "driving like a douchebag," while it does piss off everyone else on the road, isn't really the one and only cause of poor MPG. Plenty of ordinary people who (at least like to think they) aren't douchebags waste all kinds of gas driving in ways that don't annoy too many people at all. If you just push down the pedal a certain amount when the light turns green and hold it there until you reach your intended speed, the transmission (automatic of course) is just going to shift when the PCM tells it to, and the PCM isn't usually as good as you are at figuring out the best throttle modulation for a given situation.

If you're stopped, and you know you're just gonna have to stop again in 200 feet, of course you're just gonna putt on up there as gently as you safely can, right? But if you've got a mile of open road ahead of you till the next light, or whatever, I've found that it's actually helpful to be slightly heavier with the right foot until you get to your intended speed, then let off nice and quick which'll (hopefully) tell your transmission that you want to be in top gear NOW. Works on my car, anyway. Remember that since instantaneous fuel consumption is on an exponential curve, it doesn't increase that sharply on the bottom half of the tachometer, so by getting to your cruise speed with a little more punch but also keeping your engine at civilized speeds, you'll spend a bunch more time putting along at 1300 rpm or whatever, and even a gas-chugging V8 doesn't drink too deeply at those speeds. There's a editor of Road & Track magazine who'll back me up on this, in I think their August '08 issue.

Another tip for those of us with automatics: the torque converter has a lockup feature (on just about every car built in the last 10-15 years, and still a big portion before then) which engages at low engine loads in top (usually, and in my case, 4th) gear, turning a fluid connection into a mechanical connection, increasing efficiency and (surprise!) dropping RPM by a couple hundred. I find that the lockup doesn't engage in my car until I'm doing about 70 km/h (remember, I'm one of those Canadian folk) which is... 40-42 mph? Roughly? So when I'm driving around town and not on some neighbourhood residential street, I try to get to that speed reasonably quickly, because that's the speed where I'm in the highest gear at the lowest RPM = biggest mpg!

So, really, I don't bother with these maybe-true-but-how-effective? types of fuel saving measures like filling up in the morning, etc. Besides, in Canada, fuel is more often than not dispensed at temperatures below 60 degrees F (which is the standard that U.S. pumps use for volume calculations) and because of this, the gasoline companies installed pumps that compensate for temperature differences, otherwise we'd be getting more than we paid for (go figure). And all the extra time you'd spend at gas stations, or driving to gas stations, by avoiding stations that are being filled, or keeping your tank half full? Cars (and stations) have fuel filters for a reason, and the same goes for EVAP canisters etc. The easiest, and (who knew?) most effective ways of getting the best mpg out of whatever you're driving are revising your driving habits to those that are proven to work, not those that people throw at you with numbers and percentages. Sure, you're thinking: "Isn't that what you're doing right now?" Well... yes and no. I've tried (and had success) with the stuff I'm suggesting, and I've got a source other than hearsay and popular opinion for most of it.

In the end, though, just use trial and error. Bring a notepad with you and use your trip odometer. After six or seven fill-ups, you should be figuring out what's giving you lower mpg on one tank and higher on another. Try out different driving habits and see what they do to your consumption. I've gotten my '03 Nissan Sentra to run consistently at 27-28 mpg combined, which for me is about 75/25 city/highway. I've had a few tanks get me as high as 30. These were figures I calculated when I was using this car to deliver auto parts for nine hours a day, sometimes 200-300 lbs worth at a time.

If you want to save gas, get a 1987 Buick Grand National. V6, turbocharged, got a lot of power, and gets good gas mileage.

...All I know is this: I WANT ONE. XD

rrrrrright. Just drive smart and you'll save at least 1-2 mpg.

I came up with something to add. Draft off of trucks, not only will you get better mileage, but they will too.



There is one around here for sale, but it's expensive. (17K, rahter steep for one of those in my books, even if it's in excllent shape)

There's a whole bunch of Grand Nationals at one garage that we pass a lot... And there's about 2-3 of 'em that are for sale...

This post has been edited by Sabrestrike: Aug 3 2008, 04:05 PM