General Maxima Discussion This a general area for Maxima discussions for all years. For more specific questions, visit one of the generation-specific forums.

The Official increase your gas mileage thread.

Old 07-02-2008, 10:41 AM
  #41  
dot dot dot ...
iTrader: (22)
 
NmexMAX's Avatar
 
Join Date: Dec 2000
Location: Santa Fe, NM
Posts: 34,589
Damn crazy hypermilers
NmexMAX is offline  
Old 07-02-2008, 10:57 AM
  #42  
SuPeRmOd
iTrader: (6)
 
NismoMax80's Avatar
 
Join Date: May 2004
Posts: 6,375
Originally Posted by NmexMAX View Post
Damn crazy hypermilers
that's right bish. check out my new fav forum:
http://ecomodder.com/forum/

list of 105 tips >*
http://ecomodder.com/forum/EM-hyperm...ecodriving.php

Last edited by NismoMax80; 07-02-2008 at 11:00 AM.
NismoMax80 is offline  
Old 07-02-2008, 11:07 AM
  #43  
dot dot dot ...
iTrader: (22)
 
NmexMAX's Avatar
 
Join Date: Dec 2000
Location: Santa Fe, NM
Posts: 34,589
I figured you would be one of them types. I remember you saying a loong time ago something about, when coming to as top, let off the throttle waaay before you need to stop, as in you will need to use less brakes, and you'll save fuel. I shoulda' known back then
NmexMAX is offline  
Old 07-02-2008, 11:23 AM
  #44  
Member
 
Join Date: Mar 2008
Location: 631
Posts: 64
good tips
Maxxedout01 is offline  
Old 07-02-2008, 11:27 AM
  #45  
SuPeRmOd
iTrader: (6)
 
NismoMax80's Avatar
 
Join Date: May 2004
Posts: 6,375
Originally Posted by NmexMAX View Post
I figured you would be one of them types. I remember you saying a loong time ago something about, when coming to as top, let off the throttle waaay before you need to stop, as in you will need to use less brakes, and you'll save fuel. I shoulda' known back then
part of it is to help the car last longer as well...
but i hypermile as much as i can stand so when i go WOT occasionally i feel less guilty
my avg mpg of 22 is likely from getting 30 mpg sometimes and 14 mpg other times
NismoMax80 is offline  
Old 07-02-2008, 12:09 PM
  #46  
Senior Member
 
Join Date: Jun 2005
Location: Philadelphia, PA
Posts: 2,898
Originally Posted by ptatohed View Post
Rad! I met my goal of 450 miles on a tank. I had 454.2 miles on my trip odo. before I filled up today. I filled up with 16.4 gallons. Mileage = 27.7 MPG. Not too bad. That is following most of my rules, but not all. My '96 Maxima. 180,000 miles. Well maintained. 70% highway. AC on almost 100% of the 450 miles. Included a weekend of carrying 4 passengers around. I always do 60 MPH on my way home but I always snooze one too many times in the morning and need to speed at 80+MPH to work. So, I'm sure I could do better if the weather was cooler (less AC) and if I could get up earlier! lol
thats pretty good.. do you drive an auto or manual? if manual, what gear are you in when cruising at 60?
wyche89 is offline  
Old 07-02-2008, 07:28 PM
  #47  
I'm watching you, boy...
iTrader: (21)
 
SilverGLE's Avatar
 
Join Date: Jan 2006
Location: Knoxville, TN
Posts: 2,262
Very good advice... I actually started forcing myself to go easier on the gas from starts and saw my mileage go up by 1-2 around town on that alone. I tried to instill that virtue into my lead-footed, broke ex-gf. She complains about gas prices and the lack of money, but has only slightly lightened her foot... :-/

I use my cruise religiously... I drove from Knoxville, TN to Richmond, VA and got 25.9 MPG (AT). Driving around the Eastern Shore where the SL is 55ish, I've been getting 23-26, with the 23 being when I was slightly heavier on the gas.
SilverGLE is offline  
Old 07-03-2008, 03:38 PM
  #48  
I'm watching you, boy...
iTrader: (21)
 
SilverGLE's Avatar
 
Join Date: Jan 2006
Location: Knoxville, TN
Posts: 2,262
Thought of another good one... When using the cruise control (mainly on automatics), don't use resume until you're within 1-2 MPH of your set speed. This will keep the AT from downshifting unnecessarily (like mine loves to do).
SilverGLE is offline  
Old 07-06-2008, 12:27 AM
  #49  
Licensed to Spell
Thread Starter
iTrader: (12)
 
ptatohed's Avatar
 
Join Date: Feb 2001
Location: Murrieta (southern California)
Posts: 4,510
Originally Posted by NismoMax80 View Post
i already do almost all of these.

for the tire pressure it is more accurate to follow Nissan's PSI when cold then to fill to the Max when hot. that makes almost no sense at all. how do you know you have them at the hottest? just check them in the morning and fill to what the manual states.



The 2 I have wanted to do but would like to see more information is the weight reduction and aerodynamic under body panels. I bought polycarbonate, but hit a road block on how to install it while removing it easily for maintenance.

adding mods usually adds more weight. I used to take out my spare, but that is worth more the one time i might need it than gas saved. maybe i'll think about only leaving it in for long trips only.





Here is a tip not many think about.


WAX


may seem silly, but you will have a lot less drag with a clean and waxed surface. It also motivates you to keep her looking clean. 2 birds with one stone.
I'm not so sure I agree with you about the tire pressure. But, again, I am open to changing post #1 if I can be convinced. One, I'm not even sure what you mean by Nissan's recommendation when cold. Where is this listed? And, two, even if there is a Nissan recommended cold PSI, who still has their original tires? Or even their original tire size? And how can you fill up your tires cold unless you have a compressor at home? I don't think there is anything wrong with going for a normal drive and then filling your tires up to the max PSI.

Weight reduction is a biggy. And not that hard to do. And, quite often, it's free! I did a lot of weight reduction to my '99 for acceleration reasons (I should do it to my daily driver '96 for fuel economy reasons). If you are creative and study your car from bumper to bumper, you can remove a lot of weight. I won't go into the how-to on this thread but you can easily remove 100-200 or more pounds.
The aerodynamic under body panels is something I am too just getting into. I already bought my material from Home Depot. I will be planning and installing them soon. What is polycarbonate?

I disagree that doing mods usually add weight. Replacing a stock Y-Pipe usually shaves some good weight. A catback? Underdrive pulley. Lighter rims. Etc.

I'm going to refrain from adding wax to the first post, sorry.
ptatohed is offline  
Old 07-06-2008, 12:40 AM
  #50  
Licensed to Spell
Thread Starter
iTrader: (12)
 
ptatohed's Avatar
 
Join Date: Feb 2001
Location: Murrieta (southern California)
Posts: 4,510
Originally Posted by Mr****s95SE View Post
Cruise Control is better than a steady foot. Bumps and imperfections in the road can cause certain jumps in RPM consistency using your foot. Use Cruise Control when you can.

btw, ptatohead: great suggestions, although I still drive like I usually do. Nothings changed except for my diminishing wallet :P
I agree. CC is a good thing. The few exceptions is when you are going down hill. The cruise seems to coast...accelerate....coast....accelerate... I turn off the CC and just use a steady foot. Also, if I have the CC on but an uphill is approaching, I turn off the CC for 2 reasons. 1, to gather a little extra speed and 2, to allow my car to decrease in speed a little up the hill so as to avoid a downshift. But on flat ground, always use the CC.

Come on Mr. ****. Just try it for one tank of gas.




Originally Posted by coyuma View Post
I don't know, but wouldn't you waste more gas by starting your car since the fuel pump pressurizes your lines and feed your injectors for the car to start?? That is if your are only going to stop the engine for a few seconds.
Stop the engine for a few seconds? Again, the tip states 30-60 seconds.



Originally Posted by NismoMax80 View Post
check the post in my signature. more and more people are improving their MPG by making the front and underbody more aerodynamic.


i wish you would correct your advice on tire PSI. they need to be checked cold for the manufacturer's cold PSI. going below this can hurt MPG, but studies show over inflating to the MAX PSI does not benefit MPG.
Thanks for the link. Already responded to the tire PSI.
ptatohed is offline  
Old 07-06-2008, 12:56 AM
  #51  
Licensed to Spell
Thread Starter
iTrader: (12)
 
ptatohed's Avatar
 
Join Date: Feb 2001
Location: Murrieta (southern California)
Posts: 4,510
Originally Posted by wyche89 View Post
thats pretty good.. do you drive an auto or manual? if manual, what gear are you in when cruising at 60?
Auto. It's in 4th. If I had a stick, it would be in 5th.



Originally Posted by SilverGLE View Post
Thought of another good one... When using the cruise control (mainly on automatics), don't use resume until you're within 1-2 MPH of your set speed. This will keep the AT from downshifting unnecessarily (like mine loves to do).
Very good point. And this should be 1-2 miles over. I noticed that if you are under your cruise control speed and you hit 'resume', the car accelerates pretty hard to get back to speed. If I have my CC on but I need to slow down for any reason (via coasting, not braking ), I always feather my gas back to 1-2 miles over my CC speed and then hit 'resume'.
ptatohed is offline  
Old 07-06-2008, 01:02 AM
  #52  
Licensed to Spell
Thread Starter
iTrader: (12)
 
ptatohed's Avatar
 
Join Date: Feb 2001
Location: Murrieta (southern California)
Posts: 4,510
Originally Posted by mgp429 View Post
Thanks, any little bit helps right now.
You're welcome. But I think if you follow all/most of the tips, it's more than a "little bit".
ptatohed is offline  
Old 07-21-2008, 12:41 PM
  #53  
Super Moderator
iTrader: (43)
 
The Wizard's Avatar
 
Join Date: Feb 2002
Location: Southern California
Posts: 15,530
Thanks for taking the time to type and share all this info with us Josh. Good stuff!

BTW, what's your basis for tip #4? Have any factual data/tests to share?
The Wizard is offline  
Old 07-24-2008, 03:00 PM
  #54  
Junior Member
 
Join Date: Dec 2007
Posts: 19
Isn't it ridiculous how quickly gas prices adjust to higher oil prices and how slowly they adjust to lower oil prices?
PGT186 is offline  
Old 07-28-2008, 01:07 AM
  #55  
Senior Member
iTrader: (1)
 
Join Date: Jun 2005
Location: nowheres, CA
Posts: 3,301
Originally Posted by Mr****s95SE View Post
Cruise Control is better than a steady foot. Bumps and imperfections in the road can cause certain jumps in RPM consistency using your foot. Use Cruise Control when you can.
I prefer to work on keeping a steady foot, it has the added bonus of keeping me awake on long trips. With my foot I can keep it at pretty much the same TPS and LOD (+ or - 1 or 2 TPS and 2-4% LOD difference on big bumps). All it took was some practice on my part to keep this precision. The last trip on the freeway that I took, I was able to get an average of 33 MPG(not too impressive, I am aiming for 40) while going 55-60MPH on the highway and keeping a very steady foot(70 mile round trip with some street driving as well). This is on a 2000 maxima GLE automatic. My best MPG so far with 75% city(stop and go) and 25% highway was 24.5MPG(274.2 miles driven and 11.155 Gallon fillup). This is about an 8MPG increase from my previous combined MPG

Last edited by Mr. Blue Sky; 07-28-2008 at 01:13 AM.
Mr. Blue Sky is offline  
Old 07-29-2008, 01:51 PM
  #56  
Licensed to Spell
Thread Starter
iTrader: (12)
 
ptatohed's Avatar
 
Join Date: Feb 2001
Location: Murrieta (southern California)
Posts: 4,510
Originally Posted by The Wizard View Post
Thanks for taking the time to type and share all this info with us Josh. Good stuff!

BTW, what's your basis for tip #4? Have any factual data/tests to share?
Thanks Jimmy James.
#4, huh?
4.) Keep your car aligned. A poorly aligned car will spend more gas. It is more work on your car to drive straight when it is being pulled to the left due to a miss-alignment.

Any factual data or tests? Probably not. I believe I read it in a magazine for tips on how to save gas. I do believe it was the monthly AAA magazine they mail out to members. But, none the less, I thought it was common sense. Taking the path of least resistance will always require less work. Less work = less gas. If your car "wants" to pull right, then 'right' is the path of least resistance. If you need to counter steer your car the whole time, you are increasing the rolling resistance and work required by the car. Make sense?



Originally Posted by PGT186 View Post
Isn't it ridiculous how quickly gas prices adjust to higher oil prices and how slowly they adjust to lower oil prices?
Kind of like how when you buy something - you better believe your credit card is charged that day. But when you return something, you hear "allow 30 days for the credit to show up". Huh??? lol
ptatohed is offline  
Old 07-29-2008, 02:28 PM
  #57  
Senior Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Norcal
Posts: 362
Originally Posted by ptatohed View Post
Kind of like how when you buy something - you better believe your credit card is charged that day. But when you return something, you hear "allow 30 days for the credit to show up". Huh??? lol
Quoted for the truf... Big companies make mad money by this one.
Norkoastal is offline  
Old 07-29-2008, 05:05 PM
  #58  
Senior Member
iTrader: (10)
 
Join Date: Nov 2004
Location: Santa Barbara, CA
Posts: 9,107
I drove 300 miles in 3 hours and still got 23mpg

Also, antti is right, downshifting > neutral in terms of mpg. You are using gas when idling, you are not when in gear at 3000rpm and 0% TP. Of course, if you're a throttle blipper, it's a different story.
MorpheusZero is offline  
Old 07-29-2008, 09:17 PM
  #59  
Junior Member
 
Join Date: Jul 2008
Location: Greenwood Lake NY
Posts: 24
Nice write up ptatohed.

I am going to disagree with lowering your speed to attain better gas mileage. The reason being that gearing, coefficient of drag, and engine efficiency at a given rpm all play a factor in what mileage you get at what speed.

Both my best friends 84 vette, and my Dad's 02 SLS get their best mileage at 71 mph, according to the computer.

My 03 2500HD Silverado also does better and higher speeds. I see no difference between 60 and 75 mph on the highway, and I keep track very well. Averaging 12.6 miles to the gallon, you can bet I am searching for ways to get better gas mileage out of that beast.

Some more information is needed to calculate Maxima's most efficient speed on the highway, before either one of us can say 55mph is more efficient than 65mph.

Secondly, I Also get better gas mileage using my right foot, over cruise. You should know this because in your ideas, you kind of contradict yourself. You say it is better to speed up before a hill, but cruise control won't do that for you. Also cruise control on some cars, on certain grades of down hill, will not function properly, and constantly search for the correct speed by applying gas, and letting go several times per minute, (it seems as thought the minimum amount of gas the cruise can apply is too much to maintain correct speed) where as if you were using your foot, you would just coast, or as I do, on very big hills, I put it in neutral (which might go against the engine braking theory posed by others here in this thread). I will even use the hill to pick up a little extra speed, so I can coast part way up the next hill.

For most people (the majority of the public that does not know how to drive, and is probably scientifically/mechanically illiterate/challenged), cruise control will give them better gas mileage. I watched a guy just 2 days ago on this long 2 mile down hill, hit his gas and brake about 2 dozen times, while I just coasted in neutral the entire way.

I Want to add something. In my 94 Astro, that I bought with 17k on it, and selling it now with 225k, I noticed a 1.5 mpg increase by switching to amsoil synthetic, and prolong superlube. I took my readings while commuting 60 miles to work, over 25,000 miles of driving. Always filling up at the same station, using the same pump (which is critical in trying to figure out mileage, at different stations and pumps, you can get more or less gas in your car). When I put those oils in at 175k, I went 13k only burning one quart of oil. Amsoil claims you can go 25k with one filter change. I did it, and that engine still does not burn oil. I am convinced that oil is good. I saw a .5mpg increase in my 2500HD with the same oil.

Another tip I do is, if I know I am going to be climbing a large hill, I turn the A/C off going up the hill, and then crank it back up on the downhill, and use the engine braking to run up the compressor again. Probably doesn't save all that much, but everything counts. Plus it keeps the engine a little bit cooler, and less strain on everything.

I hope I expressed myself clear enough
antslake is offline  
Old 07-30-2008, 12:57 PM
  #60  
Licensed to Spell
Thread Starter
iTrader: (12)
 
ptatohed's Avatar
 
Join Date: Feb 2001
Location: Murrieta (southern California)
Posts: 4,510
Originally Posted by antslake View Post
Nice write up ptatohed.

I am going to disagree with lowering your speed to attain better gas mileage. The reason being that gearing, coefficient of drag, and engine efficiency at a given rpm all play a factor in what mileage you get at what speed.

Both my best friends 84 vette, and my Dad's 02 SLS get their best mileage at 71 mph, according to the computer.
Sorry, antslake. I can't, by this example alone, change my recommendation to lower top/cruising speed for the benefit of increasing MPG. All the research I have done indicates that lower speed results in higher MPG. I do not think that it is an incorrect statement to say that most cars will get higher mileage at 60 than at 75. From my research, there is a platue from 40 mph to 60 mph with speeds under 40 and over 60 results in a drop off of MPG.





Originally Posted by antslake View Post
Secondly, I Also get better gas mileage using my right foot, over cruise. You should know this because in your ideas, you kind of contradict yourself. You say it is better to speed up before a hill, but cruise control won't do that for you.
I don't see a contradiction at all. Use your cruise control, then, if (if) you come across a hill, gather up speed ahead of time. I also say to use cruise control but to brake slowly and smoothly at stop lights/stop signs - is that a contradiction too?


Originally Posted by antslake View Post
Also cruise control on some cars, on certain grades of down hill, will not function properly, and constantly search for the correct speed by applying gas, and letting go several times per minute, (it seems as thought the minimum amount of gas the cruise can apply is too much to maintain correct speed) where as if you were using your foot, you would just coast, or as I do, on very big hills, I put it in neutral (which might go against the engine braking theory posed by others here in this thread). I will even use the hill to pick up a little extra speed, so I can coast part way up the next hill.
I agree with you. And I believe I already said that cruise is best on flat ground but that a right foot is better up/down hills.




Originally Posted by antslake View Post
I Want to add something. In my 94 Astro, that I bought with 17k on it, and selling it now with 225k, I noticed a 1.5 mpg increase by switching to amsoil synthetic, and prolong superlube. I took my readings while commuting 60 miles to work, over 25,000 miles of driving. Always filling up at the same station, using the same pump (which is critical in trying to figure out mileage, at different stations and pumps, you can get more or less gas in your car). When I put those oils in at 175k, I went 13k only burning one quart of oil. Amsoil claims you can go 25k with one filter change. I did it, and that engine still does not burn oil. I am convinced that oil is good. I saw a .5mpg increase in my 2500HD with the same oil.
Thanks for the input, I appreciate that.



Originally Posted by antslake View Post
Another tip I do is, if I know I am going to be climbing a large hill, I turn the A/C off going up the hill, and then crank it back up on the downhill, and use the engine braking to run up the compressor again. Probably doesn't save all that much, but everything counts. Plus it keeps the engine a little bit cooler, and less strain on everything.
Good tip. And I do believe that I mentioned this tip. I too think it's wise to "cycle" your AC. I didn't really understand what you said from "... and use the engine braking ....." on.

Originally Posted by antslake View Post
I hope I expressed myself clear enough
Crystal. Thanks.
ptatohed is offline  
Old 07-30-2008, 02:18 PM
  #61  
Senior Member
iTrader: (10)
 
Join Date: Nov 2004
Location: Santa Barbara, CA
Posts: 9,107
He means that he's at 0 throttle going downhill so he's using momentum instead of fuel to turn the AC compressor, momentum that would otherwise be wasted by applying the brake if engine braking wasn't sufficient to keep a reasonable speed down the hill
.
MorpheusZero is offline  
Old 07-31-2008, 02:30 PM
  #62  
3.5 Swapped!
iTrader: (32)
 
95maxrider's Avatar
 
Join Date: Nov 2001
Location: Herndon, VA
Posts: 7,182
Two things in your list, IIRC, are inaccurate.

First, rolling down the windows is always better than using the AC. I can't remember where I read it, probably a magazine, but using the AC can decrease mileage by up to 20%. I'm not good with physics, but I'm pretty sure the resistance from rolling down windows won't decrease mileage by 20%. I'll try to find the source of this.

EDIT: I found a link with some good info
LINK
overall mpg averages:

AC/ windows closed: 54.25mpg
no AC/ windows closed: 60.6mpg
no AC/ 2 windows venting 6": 58.6mpg

Ok, it's not 20%, but it's 10%. Looks like the windows only take away 2-3%.

Second, about tire pressure. Again, I'm not sure where I read this, probably another magazine. But it said that increasing tire pressure 3 psi over the recommended limit can increase mileage by something like 2%, 6 psi= 4%, etc. Until I find the source for this, just make sure your tires are at least inflated to the recommended maximum.

EDIT: It's only anecdotal evidence, but enough people seem to agree with him, so I'll post this LINK
It seems to verify my claim that you can safely over inflate your tires (~40 psi) to improve mileage.

I've done a lot of maintenance to my car recently and have gone from 17 mpg avg to 25.8. I fixed a bunch of vacuum leaks, did a carbon cleaner, cleaned my air filter and left my tires at 40 psi after my last auto-x. With AC on half the time, doing 80 mph, I got almost 26 mpg, which is really good in my books. If I went slower and didn't use the AC I bet I could get 28.

About going slower= better mileage, I was wondering about how the car's powerband affects this. Let's say peak torque is made at 3000 rpm. Would the car operate more efficiently on the highway at peak torque or at a lower rpm where the engine has to do more 'work' to maintain speed or get up a hill. I wonder...

Last edited by 95maxrider; 07-31-2008 at 02:44 PM.
95maxrider is offline  
Old 07-31-2008, 08:49 PM
  #63  
Junior Member
 
Join Date: Jul 2008
Location: Cambridge, ON
Posts: 23
Good stuff. Was just reading Consumer Reports, and in their tests running the A/C in their Camry at 65mph reduced the mileage by 1mpg, and rolling down the windows at 65mph wasn't even measurable. I won't even TRY to calculate how much gas you could save by waxing your car ;-)

For me, the biggest savings come by driving smoothly and keeping at the speed limit. It really makes a difference, especially on long highway trips.
maximullins is offline  
Old 08-06-2008, 12:57 AM
  #64  
Member
iTrader: (2)
 
Join Date: Dec 2007
Location: Bay Area
Posts: 63
http://www.metrompg.com/posts/pulse-and-glide.htm

I'm surprised no one mentioned this before... Pulse and glide.

I've gotten 28 mpg out of my car, driving from SF to San Diego. Basically, you choose a target average speed, and then accelerate beyond that speed, shift into neutral, and let the car coast to below the target speed. For example, I want an average of 65 mph. I accelerate to 70 mph (pressing the accelerator just enough so that my 4 sp. auto tranny is just on the verge of shifting into third), shift into neutral and coast to 60 mph. Make sure the coast is longer than the acceleration period, though, otherwise there's no point to this...

This is easier w/ a manual tranny, since you have more control over the engine rpm.

Anyone else try this before?
muravei2 is offline  
Old 08-06-2008, 05:53 AM
  #65  
Junior Member
 
Join Date: Jul 2008
Location: Greenwood Lake NY
Posts: 24
Originally Posted by muravei2 View Post
http://www.metrompg.com/posts/pulse-and-glide.htm

I'm surprised no one mentioned this before... Pulse and glide.

I've gotten 28 mpg out of my car, driving from SF to San Diego. Basically, you choose a target average speed, and then accelerate beyond that speed, shift into neutral, and let the car coast to below the target speed. For example, I want an average of 65 mph. I accelerate to 70 mph (pressing the accelerator just enough so that my 4 sp. auto tranny is just on the verge of shifting into third), shift into neutral and coast to 60 mph. Make sure the coast is longer than the acceleration period, though, otherwise there's no point to this...

This is easier w/ a manual tranny, since you have more control over the engine rpm.

Anyone else try this before?

I think this would be ineffective. I do own and operate a HVAC business, and I specialize in energy efficiency. Contrary to what one would think, oil burners, gas burners, Central air units are most efficient (percentage wise) when running all the time. It's city driving as opposed to highway driving. Using your gas to accelerate all the time would waste more energy than just managing your speed at a constant, coasting idea included.

I did mention before though that coasting down hills is part of my energy management.

I just wrote the preceding before reading your link. Some quotes from your own link:
The Prius is particularly excellent at gliding because under most conditions when the the accelerator is released below 40 mph, the gasoline engine shuts off completely and the transmission effectively freewheels in neutral (it's actually slightly more complicated than that, but stick with me). So, while gliding, it's effectively getting infinite mpg - it's using no gas at all.
Before going into the details, I should point out that it's not a technique that can be used all the time in real world driving.
Your engine has to be off in the glide mode.

Not to mention, if you did that here in N.Y. on say......the Long Island Expressway.....you would probably have a 18 wheeler as a new back bumper fixture.

Last edited by antslake; 08-06-2008 at 05:58 AM.
antslake is offline  
Old 08-06-2008, 06:13 AM
  #66  
Senior Member
 
Join Date: Jun 2006
Location: Poughkeepsie, NY
Posts: 145
Originally Posted by ptatohed View Post
I'm not so sure I agree with you about the tire pressure. But, again, I am open to changing post #1 if I can be convinced. One, I'm not even sure what you mean by Nissan's recommendation when cold. Where is this listed? And, two, even if there is a Nissan recommended cold PSI, who still has their original tires? Or even their original tire size? And how can you fill up your tires cold unless you have a compressor at home? I don't think there is anything wrong with going for a normal drive and then filling your tires up to the max PSI.
I have heard that the recommended ratings are for "cold"... but what exactly is "cold" anyways? If it's 15 degrees out, the "cold" volume of the tire is going to be different than if its 85 degrees out, so i dont see how you could accurately measure "cold" or "hot" fill-ups anyway
20SE00 is offline  
Old 08-06-2008, 12:55 PM
  #67  
Senior Member
 
Join Date: Jul 2001
Location: state of confusion
Posts: 1,334
Originally Posted by Mr****s95SE View Post
Cruise Control is better than a steady foot. Bumps and imperfections in the road can cause certain jumps in RPM consistency using your foot. Use Cruise Control when you can.
Not always true.

You as an intelligent being with awareness of your surroundings can ease up off the throttle as you crest a hill after maintaining either the same steady pace up the hill as the CC - or by sacrificing a few mph as you climb to save a little more. Most CC's tend to accelerate as the slope flattens out because it cannot anticipate the upcoming reduction in load. CC is a constant speed device, which is not necessarily the same thing as a minimum fuel usage tool.

The best strategy might be to use CC on flat ground, while DIY'ing it up the hills. I don't know about downhill CC usage, but I would always rather have full engine compression braking available for speed control than save a couple pennies worth of fuel.


Norm
Norm Peterson is offline  
Old 08-06-2008, 01:11 PM
  #68  
Senior Member
 
Join Date: Jul 2001
Location: state of confusion
Posts: 1,334
There probably is some benefit in higher tire inflation pressures than OE sticker numbers. I am equally sure that it is a diminishing returns kind of thing, where the first 5 psi over OE sticker is worth less than being 5 psi underinflated, and each incremental 5 psi after that being worth less than the previous step. Whether this trend ever noses over and drops I don't know, but at some point it might just take more effort to bump up and roll over minor roadway irregularities than it would take to let the tread flex a little more to conform over them instead.

Of course, that ignores everything else that is a function of tire pressure, and
IM(not so humble)O hypermiling tricks such as this are short-sighted in their one-sidedness.


20SE00 - Cold inflation pressure means just that. Cold. The number of air molecules inside the tire is immaterial, since it is only the pressure they exert on the tire structure that matters. Keep in mind that the actual car behavior depends on the tire's operating temperature anyway, so if anything, the mfrs take a slight pressure increase into consideration when specifying cold pressures. Cold pressures are easier conditions for most people to duplicate than to expect them to estimate how close to fully warmed up the tires might be at any given instant. Anybody who has autocrossed much knows a bit about tire pressure increases due to use.


Norm

Last edited by Norm Peterson; 08-06-2008 at 01:17 PM.
Norm Peterson is offline  
Old 08-06-2008, 01:36 PM
  #69  
Member
iTrader: (2)
 
Join Date: Dec 2007
Location: Bay Area
Posts: 63
Originally Posted by antslake View Post
I think this would be ineffective. I do own and operate a HVAC business, and I specialize in energy efficiency. Contrary to what one would think, oil burners, gas burners, Central air units are most efficient (percentage wise) when running all the time. It's city driving as opposed to highway driving. Using your gas to accelerate all the time would waste more energy than just managing your speed at a constant, coasting idea included.

Your engine has to be off in the glide mode.

Not to mention, if you did that here in N.Y. on say......the Long Island Expressway.....you would probably have a 18 wheeler as a new back bumper fixture.
The only reason I'm really mentioning this is because I've done this over long stretches of flat road and seen much higher mpg. I can pretty much get the mpg of driving at lower speeds, like 60 mph, but have a higher average speed.

I know it seems counter-intuitive, i.e. it would seem that the acceleration would outweigh the coasting. However, that is not the case mainly because the coast period (if done properly) is about twice as long as the accel. period.

As for aggravating other traffic, yes, that is a concern. This method is only really effective over long interstates with little traffic, or at least traffic that doesn't want to eat your rear bumper.
muravei2 is offline  
Old 08-06-2008, 02:09 PM
  #70  
Senior Member
 
Join Date: Jul 2001
Location: state of confusion
Posts: 1,334
What you're counting on is that you save more during the idle time than the acceleration enrichment plus getting through the extra drag above your target speed costs. I can see that it could work, at least under the right circumstances. Might not, say, against a stiff headwind. Or uphill.

Unfortunately, I can also see where it might be illegal, never mind the aggravation to other traffic (particularly to the folks who are 100% tied to the use of CC) or extra wear & tear on the tranny when you re-engage some gear (hopefully an appropriate one, if you're driving a manual).


Norm
Norm Peterson is offline  
Old 08-12-2008, 10:37 PM
  #71  
Newbie - Just Registered
 
Join Date: Aug 2008
Location: Springfield, MO and Russellville AR
Posts: 6
Reduce weight ... drive naked.
Golferluke is offline  
Old 08-13-2008, 04:33 PM
  #72  
Banned
iTrader: (10)
 
Join Date: Dec 2002
Location: Boston Baby!
Posts: 4,205
my biggest tip is not driving.
Torgus is offline  
Old 08-14-2008, 03:43 PM
  #73  
Senior Member
iTrader: (9)
 
Join Date: Nov 2007
Location: SLC, UT
Posts: 668
Same here. Not driving helps a bunch. I've tried some of the tips and am not sure if they are legit. Also in Germany the gas is MUCH more expensive so I still feel good here in the US. I get 21 in town (96 auto) and 29 freeway @ 80+ mph
djipka is offline  
Old 08-14-2008, 05:01 PM
  #74  
Senior Member
iTrader: (4)
 
Join Date: Jan 2007
Location: Pittsburgh, PA
Posts: 2,374
Well my best way to save gas is to not drive, hehe my car is broke atm and iam driving a friends car < i need a alternator>
Professor is offline  
Old 08-15-2008, 12:50 PM
  #75  
Licensed to Spell
Thread Starter
iTrader: (12)
 
ptatohed's Avatar
 
Join Date: Feb 2001
Location: Murrieta (southern California)
Posts: 4,510
Torgus, djipka, Professor';

The entent of this thread is to increase the distance per gallon of gasoline, per mile driven. Not driving does not increase your MPG.
ptatohed is offline  
Old 08-15-2008, 01:30 PM
  #76  
Senior Member
iTrader: (9)
 
Join Date: Nov 2007
Location: SLC, UT
Posts: 668
ok. I try to keep a steady speed at steady RPM. in other words - cruising.
djipka is offline  
Old 08-15-2008, 01:35 PM
  #77  
3.5 Swapped!
iTrader: (32)
 
95maxrider's Avatar
 
Join Date: Nov 2001
Location: Herndon, VA
Posts: 7,182
Originally Posted by ptatohed View Post
Torgus, djipka, Professor';

The entent of this thread is to increase the distance per gallon of gasoline, per mile driven. Not driving does not increase your MPG.
Any thoughts on post 62? I think the info could be added to your original post.
95maxrider is offline  
Old 08-31-2008, 08:14 AM
  #78  
Senior Member
 
Join Date: May 2008
Posts: 347
I was watching Mythbusters the other night and they did an experiment to see just how much your gas mileage would increse by drafting close to an 18 wheeler.

By driving 12ft behind an 18 wheeler, they were able to increase gas mileage by 44%.
4DSCDriver is offline  
Old 08-31-2008, 09:55 AM
  #79  
Senior Member
 
Join Date: Jul 2003
Location: Jersey City, NJ
Posts: 148
I will be drafting this afternoon lol
angelmaxima is offline  
Old 08-31-2008, 10:57 AM
  #80  
Senior Member
iTrader: (11)
 
Join Date: Jun 2006
Location: Cherry Hill, NJ / Hoboken, NJ
Posts: 1,329
I draft trucks all the time, and get over 30mpg highway in my '97, with the AC on. Just gotta remember, if the road gets crappy, keep your distance. Don't want gravel cracking your windshield.

I have the manual climate control, and I was wondering what the best way to maximize efficiency is on it during the summer?

Is it better to put it on all the way cold, fan speed 1, and leave it on all the time?

Or put it halfway cold, fan speed 2, and leave it on all the time?

Or put it all the way cold, fan speed 2, and turn it on for 5 minutes, then off for 5 minutes, keeping the fan on in between?

I haven't really done enough driving to compare... basically, I'm wondering what the best combination of climate control settings is to minimize power loss of the AC compressor?
nalc is offline  

Thread Tools
Search this Thread
Quick Reply: The Official increase your gas mileage thread.


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.