Beating the EPA - The Why’s and How to Hypermile

Discussion in 'Articles' started by xcel, Jul 24, 2006.

  1. abcdpeterson

    abcdpeterson Well-Known Member

    Re: Beating the EPA - The Why’s and How to Hypermile

    Is this missing form the techniques or is it not truly a technique?
    Hang Time.

    It’s listed in the glossary,
    but not in the “Beating the EPA - The Why’s and How to Hypermile”

    -Hang Time.
    I use it as a technique a LOT. :D
  2. orionRider

    orionRider New Member

    Last edited: Dec 23, 2008
  3. orionRider

    orionRider New Member

    Re: Beating the EPA - The Why’s and How to Hypermile

    Now that I'm registered I'd like to add some other tricks I use to boost FE. I don't think they were mentioned yet. Ah, and sorry for my English. I hope you'll understand :p

    1. use narrow(er) tires! If you have the choice between narrow or wide tires, buy narrow. The less surface on the road, the less drag you create. I know it doesn't look cool, but narrow tires can let you gain as much as 10% FE.

    2. avoid special 'winter' tires if you do not absolutely need them. They are made of a softer rubber and have a lower maximum inflation than regular tires. Not only do they wear much faster and cost more, but they drag more than normal tires.

    3. heavy wheels require more power to accelerate. Some alloy wheels are actually heavier than standard iron plate wheels. Also, 5-spokes alloy wheels drag more than plain plastic covers on iron wheels. The less holes, the better the aerodynamics.

    4. most modern injection engines cut the fuel line when you let go of the accelerator (engine braking). Basically, you have zero fuel consumption when you decelerate. However, if you pull in neutral (or press the clutch pedal), the engine will just idle, which uses some fuel.
    So, when approaching that red light, just let go of the accelerator. On manual clutch cars, stay in the longest gear (5th or 6th) so the engine brakes less.
    Fuel injection restarts on its own under 1000 rpm to avoid stalling, so gear down before that.

    5. check the distance to the nearest fuel station! It can be better to fill right there on the highway than to drive an extra 5 miles to get a cheaper price where you don't have to be.
    Also, don't wait until the tank is really empty because maybe at that moment you will not drive by a fuel station and will have to drive a few extra miles to find one.

    6. get rid of ballast! Basically, the engine power is used to accelerate a certain weight to a certain speed. A lighter car will use less fuel and accelerate better when needed.
    Depending on your local conditions having a 5th tire in the trunk is just hauling 40lbs ballast around. Nowadays you can inflate a flat tire with a 'foam can', which is light and easy to use. Don't do that if you cross the desert though ;)
    All other heavy junk you can better leave home. If you commute along the same distance every day, you can also fill just enough fuel for your drive. 15 gallons of fuel weight about 120lbs. If you need only 5 gallons for the round trip to the fuel station, fill just that and spare 80lbs of weight.

    7. don't drive! Just by carefully planning your moves you can damatically cut down the costs, especially on shorter trips with a cold engine. In Europe, an average car would cost you 50cts for each kilometer, all included. This means the short hop to rent a book at the town library (20km or 12 miles return) will cost you 10 dollar. You can probably buy this book online for less than that! Try to combine moves to reduce unnecessary short trips. And of course, walking costs nothing on the very short trips...

    This one is not helping to increase FE, but also good to know:

    8. Do NOT trust the car's computer MPG indicator. Check for accuracy by filling the tank completely and resetting the daily counter and computer MPG indicator. When filling again (completely), write down the mileage and gallons, compute your MPG, then compare with what the car's computer tells. Bet you'll be surprised! Many cars (especially japanese) indicate 10% less than the real thing. The spedometer also often indicates 10% more than your real speed (eg: 55mph when you really drive 50mph).

    Hope that helps someone out there... :cool:
  4. hummingbird

    hummingbird Member

    Re: Beating the EPA - The Why’s and How to Hypermile


    I have a specific query about FASing non-hybrid manual trannies -

    To achieve a specific effective speed while FASing, it is required to speed up to a higher speed, and then killing engine, one comes to the lower speed, where the cycle repeats.

    What is the effect of having a high 'delta' between the higher and lower speed (want to keep the coasting going on as far as possible, before starting up again).

    There may be a practical limit to the higher and lower speeds, and there would be one that is dictated by physics. I am interested in the physics part of it. What would be the optimum duty cycle for any general vehicle? what percentage of the target constant speed should the higher and lower speeds should be (like say 110% - 85% etc), so that the travel at the effective speed is optimal? I am asking these questions because having a non-OBD2 compliant car, I cannot check it out quickly for myself (would require too much of experimentation / would involve too many variables interfering). I would keep 50 mph as the target speed (in fact I find 50 mph daunting for an average speed since I started FASing - I put in 45 mph on my steady excursions)

    Thanks in advance for any answers, and Wish you all Hymies a happy new year 2009!
  5. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    Highway driving: I like to keep the low end high enough to use 5th gear, and the high end low enough so it doesn't kill mileage with excess speed / rpm. In my case that works out to 40/45 on the bottom and 55/60 on the top, for a 15 mph delta.

    For low speed driving, I let the terrain and conditions dictate. In time, you get a feel for what's optimal here.
  6. griz

    griz Member

    Re: Beating the EPA - The Why’s and How to Hypermile

    I now believe to Hypermile is to be an artist behind the wheel. I have Japanese mini trucks which have 3 cylinder 660 cc gasoline engines. These trucks are a main stay in Japan used in the mountain roads, cities and hwy's. The japanese buy their gas by the liter and pay for it in yen. They get Kilometers per liter in Japan. I was told they get from 12 km to 20 km per liter of their non Ethanol gasoline.
    Here in the USA I get 26 to 38 mpg and I drive poorly. I find my self with my foot in the carburetor and hitting every stop light. A friend who drives much better then I drove a tank of gas and got 57 mpg. I am wondering what can these little trucks do?
  7. jkp1187

    jkp1187 Well-Known Member

    Re: Beating the EPA - The Why’s and How to Hypermile

    I generally agree with these, but want to add three things:

    1.) I think that if you live in a place where it snows more than one or two days a year, you're in the 'snow belt' and winter tires should be considered part of the price of driving a car. All-season tires...aren't. Winter tires aren't really that expensive compared to the price of the car, and it is always handy to have an extra complete set of tires. You may lose a little bit of fuel economy using winter tires, but you will gain a lot in terms of safety (both for you and the other people on the road with you.) You can usually get a good deal on winter tires pre-mounted and balanced on cheap steel wheels from Tire Rack, shipped straight to your door.

    2.) Regarding engine-braking and deceleration fuel cut-off (dfco), the timing of when the fuel cutoff actually happens varies from car to car. Until I bought a Scangauge, I didn't realize that during my daily drive, dfco was almost never happening, even though I was engine braking, because my RPMs were too low for dfco to engage. I have now adjusted my driving (including forced downshifts) to make sure I take advantage of it. (Corollary to #2 - get a Scangauge!)

    3.) Absolutely agree on the don't drive idea! This isn't just about walking to the store from home (people living in Suburban American can't always do this,) but also walking when you get there. How many times have you (or someone you know) driven to more than one store in the same shopping center just b/c it was at the other end of the plaza? Park centrally and walk to both places.
  8. jkash

    jkash Member

    My entire drive to work is on city streets. Accelerating slowly as pulse and glide requires, I make a lot of people behind me mad. My entire trip is 12 miles. There are at least 30 lights along the way. On a good day, I can get to work in 25 minutes. On the way home, it will take 35 to 40 minutes. My mpg is much better on the way to work. Is there a way to increase my mileage in the intense stop and go on the way home. I will often have to stop at almost every light.
  9. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    Your best bet is to try and time the lights. If you can catch the green, even at 5 mph, you'll see much better mileage than if you have a full stop.
  10. Psion

    Psion Hyper-Beginner

    I've noticed some behind me riding me on my way home from work, but then they seem to notice that I'm at a speed that allows us to make the light ahead without stopping. They usually back off a bit upon that realization.
    Try and space yourself to avoid some of your traffic stops.
    If its not illegal, I don't worry about making others mad, especially if they have alternatives around me.
  11. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Re: Beating the EPA - The Why’s and How to Hypermile

    Me, too. :)
  12. rickkop

    rickkop Active Member

    Tire pressures are a very important key to higher fuel economy. The higher the pressure, the lower the rolling resistance, the higher the fuel economy. The absolute minimum you should use is the driver’s side door or owners manual recommended tire inflation criteria. This is what the EPA and your car manufacturer sets tire pressures to during the EPA city/highway testing. MAX sidewall is what I would recommend for most as it is well within the safety limits of your car and tire and allows better FE than the pressure listed in the driver’s side door. I can discuss but cannot personally recommend upwards of 25% higher than MAX sidewall as there are legal constraints we all have to live with. That being said, 50 + #’s on a MAX Sidewall rated tire leads to even higher FE . Pros, higher FE , less tread wear, more even tread wear across the treads width, shorter braking distances in a variety of conditions, and in many cases, even better handling. Cons, higher NVH (Noise, Vibration, Harshness).

    I’m one of those old timers that always went with the manufactured recommendation psi for tires. Which for my Camry is 32 all around. Since I’ve read this article I have little by little raised my tire pressure to 40 psi and have been rewarded with an increase in mileage, while the ride still feels fine to me. This makes me want to go even higher. I notice some tires have ratings of 35psi while others have 44 psi. My Camry Hybrid has the standard Bridgestone tires on it with a sidewall number of 51psi. But I don’t know if I have the nerve or would be comfortable raising the pressure all the way up to the max sidewall rating of 51 psi. Someone told me you to take 10% of the sidewall number and I should be fine there year round summer or winter in city or highway driving. That would be about 45psi for me. Any thoughts on this and does anyone know who or how they determine the sidewall psi rating on tires? Thanks, Rick
  13. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Rick:

    ___For legal concerns, MAX Sidewall is what you should consider for all your vehicles. I have been running MAX plus 40% year-round for years with both increased FE and much lionger lasting tires. The Accord's Michelin Energy's are at 109,000 miles and still going with even tread wear all the way across.

    ___Pressures are up to you but a good premise to start would be the Driving Under Pressure (full article)

    ___Good Luck

  14. rickkop

    rickkop Active Member

    Re: Beating the EPA - The Why’s and How to Hypermile

    I just don't want to be going down a smooth flat road at highway speed and have one of the front tires let go because I had too much pressure in them. I read that article and did raise pressure to 42 and was already contemplating going up to 45. I have the original Bridgstones on my TCH and the sidewall max is 51. I've never owned Bridgestones before and just not all that sure that these tires can take it. 51 Just seems high for any passenger car tire. I was trying to find out why some passeger tires are rated at 35psi and other at 51 and who determins this number. Anyway sooner or later I'll probably come around. It just takes some of us a little longer than others. Thanks for you input, Rick
  15. diamondlarry

    diamondlarry Super MPG Man/god :D

    I'm going to join with Wayne and say that max sidewall is the legal limit that can be recommended. That said, I have been running 80psi and above (44psi max) for nearly 2 years now. The only ill side effects have been the light on the dash from the TPMS.:p
    Last edited: May 25, 2009
  16. rickkop

    rickkop Active Member

    Re: Beating the EPA - The Why’s and How to Hypermile

    Ok, I'm a believer. I took the advice here and have raised my pressure to 45 psi. Been driving this way for a few days and no problems at all. The big notable difference is how long my car will stay in ev mode. The increased rolling resistance is fantastic. I have only had this TCH a short time but with reading this forum and implimenting the tires pressures and the p&g and the other hypermiling technics I can, I am getting what I consider phonomenal mileage. 40 mpg average is almost easy. Now if I could only figure out the scanguageII xguage codes for the TCH I'd be set. After my car sits tonight, I'm going the rest of the way tomorrow and raising the tires to thier sidewall max. I never thought saving gas could be so much fun. Thanks for all the help an information. Rick
  17. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Wonderful, Rick!! We really enjoy watching our members progress -- do keep us updated. :)
  18. Tochatihu

    Tochatihu Well-Known Member

    Hi, I just wanted to mention that this thread has had 335,335 views!

    Good golly.

  19. Damionk

    Damionk DWL Lover

    Re: Beating the EPA - The Why’s and How to Hypermile

    A good portion of those is members re-reading it. I know I have read it at least 3 times myself.
  20. anniemcu

    anniemcu New Member

    Hi all.

    We've been using some of these techniques all along, like the reduced speed, gliding, stop light timing, and not accelerating up inclines if not necessary, etc., but I learned a couple of nifty things I had never though of, like taking the high position in the parking lot, and to head to the farthest destination first in cold weather. The 'face out' one is a real forehead slapper for me. Duh! Why did that never occur to me - no more wasting time, tires, gas and brakes on the back out and turn. Thanks!! My neck feels better already.

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