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A.K. Boomer
05-22-2008, 05:02 PM
$3.75 a gallon has even got me thinking what else can I do? I basically have a box stock 92 toyota tercel --- even though its rated by www.fueleconomy.gov to only get 33 highway I actually do much better than that --- at 42 to 44 highway my car does pretty well even by todays standards, But, not good enough for Mwah, I achieve better ratings for all kinds of reasons, for one having a drivetrain thats got over 220,000 miles on it helps, seals lose their grip a little, gear teeth get polished in along with bearings ect.
But nothing effects mileage more than driving habits -- and iv adapted some good ones, it takes allot of focus to keep an engine in its sweet spot and not overshoot or de-accell -- it takes slow starts and also anticipating stop lights and signs and "coasting" in (more for city mpg ratings) Even though my engine is just a little 1.5 liter it is still very responsive --- its easy to over shoot and then have to slightly back off, Iv gotten far better than an average cruise control as most of them have problems with cycling if you pay attention --- also I will out do a cruise for MPG anyways simply for the fact that some shorter hills are better to give up a little speed on and then a slow recovery on its other side rather than to "charge" up them,
On the highway it still takes much focus to keep my engine where I want it for optimum efficiency - I do keep speeds down to the average, All it takes for my car to achieve 65 mph is a very slight crack of the throttle plate, its got to be about .175" of gas floor pedal --- a touch more and your over, to little and then you have to compensate, I have found that when I dont pay attention I actually lose about 2 to 3 mpg, Its for this reason that I built what I built this morning, its a variable throttle -- it takes way more foot pedal travel at crack/open position then it does close to wide/open, it will make it very nice to have a much smoother cruise without the jumpyness of what I had, For those of you thinking that Im trying to "trick" the engine out of its fuel please understand that thats not whats this is about (sorry I had to print that -- just used to some people not getting the point) Although It will in fact make it easier to get into the "granpa" mode esp. around town.
I mapped out where I was going to ratio change the standard unit and then cut and welded it back together, It worked out very slick and everything works great throughout the range, Its very "feathery" at the top and I can dial in what i want much better, it also has a very noticeable progressive spring rate so if you want full throttle you have to put your foot into it to achieve it (much more pressure than stock because I was still limited to stock gas pedal travel I had to move the fuller throttle cable position to a closer radius to achieve close to stock full pedal travel) , At first I thought I might have to build a cable casing pivot because I thought the angles would drag the cable on the housing mount to much but its smooth as silk -- its got a teflon insert or lining and I also threw some fresh mobile 1 syn grease at it.
I dont expect to see much improvement as I was already making most of them when "in my mode" -- I still may see a little -- what I expect to see is an improvement for when I forget to focus on the pampering -- now it will be more automatic, Plus its going to be hard to tell because I just switched over to mobile 1 syn. trans lube and 0w30 mobile 1 syn engine oil, they will both save -------- what surprised me also, after the oil change this morning I went to the store to pic up some grub, came back and noticed I had to set my idle down,,, Way down,,, very nice indicator...:)

Before;

http://i146.photobucket.com/albums/r249/AK_Boomer/DSC00377.jpg

After;

http://i146.photobucket.com/albums/r249/AK_Boomer/DSC00388.jpg

Quetico Bob
05-22-2008, 05:28 PM
Very cool idea! Especially if you have owned the car for a while. One gets to know where the pedal is. Install this and maintain your habits, sure it would help. Just keeping in mind it takes a little longer to get to speed. Can't wait to see what you come up with when you get to $6 a gallon like us :eek:
Don't drive my 4x4 suburban much anymore.
Cheers, Bob

loose nut
05-22-2008, 08:45 PM
$3.75 a gallon



I can almost remember when gas was that cheap here.

Dawai
05-22-2008, 09:02 PM
Was a guy on the nightly news tonight.. he is making and selling big bicycles with a weed eater engine. NEWS said $100 for kit.. I know that can't be right.. I pay more for a part for my weedeater..

He was getting 137mpg.. I looked on the local news for the story, not there.. so I guess it was not a headliner?

Another great idea for a home shop machinist to make for money to support his "more machines" more tooling habit.. Bicycles with engines.. Imagine the diesel they sell on ebay..

GKman
05-22-2008, 09:35 PM
I used to think that mileage was very dependent on throttle finesse but I've changed my thinking. Took the wife's Toyota Solara on a 600 mi trip last weekend. It has continuous MPG readout. The big factor is grade. Hills you can barely see really hammer the mileage. A lot more throttle doesn't change mileage much, it only uses a given amount of fuel for the speed, grade and acceleration. Zero to 60 in 6 seconds, yes, 65 to 70 in a few seconds, no. Kinda like trying to walk really light on thin ice so you don't fall through.

Want good mileage? The smallest engine that will get the job done at wide open throttle. What sense does it make to put a restrictor plate (a nearly closed throttle) on an engine. Engine has to work as a vacuum pump just to get a charge in the cylinder and then there isn't much charge to expand and do work. Over-sized engines have more friction and accessory losses. Lose, lose, lose.

J. R. Williams
05-22-2008, 10:36 PM
Revise the numbers to make the playing field level... Give the mileage in Ton Miles per Gallon , not Miles per Gallon.

JRW

J Tiers
05-22-2008, 11:17 PM
At the present rate of increase, you will be paying $10 per gallon this time next year, and $20 one year later.

By August we should be north of $5 per gallon and rising.

I don't know why anyone should even consider a gasoline vehicle worth repairing, let alone diddling with, at that rate.

Let 'em rust out.

Correction............. at the present rate of increase, 17% in 3 weeks, gasoline is projected to be $54 per gallon at this time next year.......... and oil will be at $1862 per barrel..............

RetiredFAE
05-22-2008, 11:56 PM
Diesel here hit $4.68 today. A month ago today it was $3.48 at the same station, according to my log book. Guess its time to get my walking shoes resoled and get back into shape!
24 Hours after the above post the station with the $4.68 a gallon diesel raised it to $4.75 a gallon. Time to invent the cosmic radiaton collector, storage device and motor.
On a strange note, the station that carries the 120 octane fuel my 1970 Trans Am runs on, just lowered the price of it from $6.79 a gallon to $6.59 a gallon!

A.K. Boomer
05-23-2008, 12:37 AM
Even though its a variance within a variance (because after all a throttle is just a "variable") It would have been more appropriate for me to have named the title to the this thread "progressive ratio throttle"

GK man, Hills and grades will take there toll no matter what, just the matter of having to lift the vehicle vertically along with all the wind drag, Finessing a throttle does work, and depending on who's driving and their previous habits can have anywhere from mild to extreme results,
Having an engine small enough thats designed to run full throttle is a pipe dream in the practical world, because we only use a fraction of an engines rating to do most of the drive time (cruise down the highway) it means we have to have overkill or we would never get over any hills (or where I live up any mountains) never be able to tow anything or load anything, never be able to get out of the way when pulling out in traffic and on and on,
Dont want to pay the dividend of having an engine ran as a suction pump?
Get a diesel --- most are now designed with wide open full bore as much as they can get their pistons on, So no more suction problem --- but --- Now even when the demand is low your compressing an incredible amount of air volume just to light off the amount of fuel that 1/20th the air could have burned efficiently -- now instead of losing it to suction your losing it to uneeded compression volume, but its needed to keep the ratio up and light off the fuel, so whats a girl to do?

Variable displacement anybody?

Actually, future compromises will be more and more evident, Even in the state of colorado I could drop another 200 CC's and run a 1.3 liter instead of a 1.5,
Im in agreement as i think everyone would be - that up to a practical degree smaller is better, But --- you get to high altitude in the summer with a little P-shooter like mine and your thankful for the most part thats its always so much cooler up there cuz even with a 1.5 the cars such a dog that running the A/C would teeter on holding up traffic, But then again, when people have to start walking instead of driving the entire A/C argument goes right out the window.

JRouche
05-23-2008, 12:49 AM
At the present rate of increase, you will be paying $10 per gallon this time next year, and $20 one year later.

Ouch!! That would hurt.. I dont drive much anymore after retirement. We were spending about 270 a month on gasoline, easy to track cause we use a card. Thats when I was working. Its still about 270 a month!!! Next my wife is gonna have to retire to keep it down LOL Oh wait, she works outta the house, doesnt even drive to work.. Oh no, we are in trouble. Guess we are gonna have to take the kids outta school cause I think thats where the gas is going, driving the kids to school. Ill home school them, teach them how to run a lathe LOL JR

derekm
05-23-2008, 04:02 AM
$3.75 a gallon



I can almost remember when gas was that cheap here.
A gallon! we pay that per litre now

speedy
05-23-2008, 06:41 AM
91 octane has just gone NZ$2.00/litre last night. That is $9.00 for a real gallon.
Damn speculators!
Damn polies!

A.K. Boomer
05-23-2008, 08:42 AM
Geeze Oh pete, I hope I didnt sound like I was complaining :eek:

Many people are adapting already and looking for alternatives, Iv never seen so many little vespa's and mopeds in my little town, Of course, whats going to happen come winter...

JRW's got a good point, if you do the math the little one person haulers are fuel hogs, they have little four strokes that do a little better (but I guess there gutless), anybody know of a little 50cc turbo diesel on the market?, I could see adapting that to a pedal bike and having some fun with it. Its about as close as you can get with underating an engine yet also having it have the capability of supplying much more than its standard displacement, it is the real beauty behind the turbo diesel.

john hobdeclipe
05-23-2008, 09:28 AM
Read an article in some outdoor magazine a few weeks ago about how to get better fuel mileage in your vehicle. Two of their points stuck in my head.

The first was just plain stupid. They said to ignore the tire pressure information supplied by the vehicle manufacturer and to always run your tires at the maximum pressure shown on the tire sidewall.

But the second point makes sense: "Drive as if you had no brakes."

Dawai
05-23-2008, 09:50 AM
Ya want to get into it?

A tiny motor running a energy storage system with a "look ahead" gps system.. a 7hp engine could pull a small car if 7-10hp was stored somehow. In braking, energy lost could be restored to system, climbing a hill? engine would run ahead of time to build to top level power to zoom over it.

Honda has went to servo controlled throttle valves.. your foot feed goes to the computer.. the computer tells the car's engine what to do. A simple economy switch could be added to the ecu, and be available for FULL POWER when needed. No more worry ing about the feathering of the throttle.. AND.. why not have "steps corresponding to speed limits".. the computer could accellerate to the proper speed?
GO down in 5mph clicks? Pretty soon you'd be able to run around town, all the traffic lights geared to speed limits so you lost less time zooming up to park and wait?

A.K. Boomer
05-23-2008, 10:15 AM
Dave -- I really think your hitting on the next phase as far as controlling the controller, we have a multitude of sensors adjusting the mix hundreds of times a second, yet there's no control over some hillbilly who likes to blast past his mark and then actually apply the brakes all while on an open highway, Tough one to police though, and the more systems you get involved the more chance of someone pumping a deer into the cab because the computer took away a valuable option that wasnt needed 99.98% of the time,

As far as an energy storage system, Yes and no, depends where you live, its of course already being done with the synergy drive vehicles, they do make sense in the city, they dont make much sense on the highway and they eat it bad where I live, We have area's that require a hundred miles of mostly all uphill travel, the synergy hybrids fall on their face, they deplete their storage system, they then have to drag uphill two separate drive mechanisms (electric motor and gas engine) WITH two separate storage means (batteries and gas) and also a separate generator plant Or synergy brake/drivetrain to turn the electric motor into said gen. plant, and they have to do it all with one de-tuned gas engine, the results are very poor economy while holding up traffic, The other factor is all the resources it took to build such an abortion, People dont realize that it all depends on where they live and what the vehicle will be used for (although dont expect the guy who's clad in polyester and selling the vehicle to tell you that), Keep it simple stupid is a good rule of thumb, There's people spending all kinds of money to use up more resources just to burn more fuel and they think their actually "doing the right thing"...

kendall
05-23-2008, 11:56 AM
Read an article in some outdoor magazine a few weeks ago about how to get better fuel mileage in your vehicle. Two of their points stuck in my head.

The first was just plain stupid. They said to ignore the tire pressure information supplied by the vehicle manufacturer and to always run your tires at the maximum pressure shown on the tire sidewall.

But the second point makes sense: "Drive as if you had no brakes."


In actuality, the automakers recommended tire pressure is intended for comfort, inflating the tires somewhere between the automakers and tire makers pressures will -normally- result in better mileage and longer tread wear.
Auto makers have two things in mind with tire pressure (among others) basic comfort and smoothness of the ride and elimination of road noise. Those are the two things that are helped the most by low tire pressure.

I've always found mileage and handling to be helped with higher pressure.
My explorer went from 19 to 20mpg on good days, to a reliable 22 to 23mpg (I can count on it) by going from the oem 35 to 40psi, takes corners much better, and gives better mileage. I do have road noise from the tires, and a stronger feel for the road but it feels positive when changing lanes on the freeway, and no longer creeps leeward in crosswinds, and getting the equivelent of 2 - 3 gallons free per tank I can live with it. When I experimented I was driving up to 1000 miles a week, now I don't drive as much but it costs as much to go 1/4th the distance so it still helps.

Quick simple test is to air up to the automaker's recommended pressure, then hand push the car on flat concrete, then go to the tire manufacturer's pressure and do the same.

another mileage tip, if you have a manual trans that uses regular gear lube, swapping to a lighter fluid in the trans and differential and that will also return a bit in mileage.

ken.

pcarpenter
05-23-2008, 03:32 PM
Add to that the fact that their (on the soft side) recommended pressure was for the OEM tires. I went from one set of light truck (LT) tires on my pickup to a different brand and size, and the "full rated pressure" is a good ten pounds higher on the new tires. Granted, LT tires run at a higher tire pressure anyway, so we are talking about the difference between 55PSI and 65PSI --either of which would be a severe overinflation for a passenger rated tire.

The truth of the matter is that correct inflation pressure will vary with load....and the tire. I try to remember to adjust mine if I make a trip with the truck loaded. A tire whose maximum load rating is 2700# (at its full inflation pressure) is not going to give you a complete contact footprint filled to that pressure and with half its rated load on it. You might save in mileage by running overinflated, only to pay more still in reduced tire life.

We have become lazy and just want to be handed a single number to watch for on the gauge as we fill our tires. The best idea is to watch for wear and figure out what it takes to have even contact across the full width of the tire. this is better for mileage than running them underinflated as the auto makers tend toward. ON the other hand, its not as good for mileage as full inflation which means less tire on the road...and reduced traction as well as a harsh ride. The ideal would be to check your road force with a sensor to see that its the same across the whole tire...but none of us have them.

Paul

john hobdeclipe
05-23-2008, 05:50 PM
The truth of the matter is that correct inflation pressure will vary with load....and the tire. I try to remember to adjust mine if I make a trip with the truck loaded. A tire whose maximum load rating is 2700# (at its full inflation pressure) is not going to give you a complete contact footprint filled to that pressure and with half its rated load on it. You might save in mileage by running overinflated, only to pay more still in reduced tire life.

We have become lazy and just want to be handed a single number to watch for on the gauge as we fill our tires. The best idea is to watch for wear and figure out what it takes to have even contact across the full width of the tire. this is better for mileage than running them underinflated as the auto makers tend toward. ON the other hand, its not as good for mileage as full inflation which means less tire on the road...and reduced traction as well as a harsh ride. The ideal would be to check your road force with a sensor to see that its the same across the whole tire...but none of us have them.

Paul
Absolutely true...this is why I felt that it was un-smart to simply make a blanket statement about running tires at the max pressure all the time. Granted it will definitely result in better fuel mileage, but the cost in terms of tire life (money and environmental impact) and safety was never mentioned.

Dawai
05-23-2008, 06:11 PM
Local Man Finds Way To Get 128 Miles Per Gallon!
Posted: var wn_last_ed_date = getLEDate("May 22, 2008 3:14 PM EST"); document.write(wn_last_ed_date);May 22, 2008 03:14 PM
Updated: var wn_last_ed_date = getLEDate("May 22, 2008 5:10 PM EST"); document.write(wn_last_ed_date);May 22, 2008 05:10 PM



Imagine being able to get 128 miles on a single tank of gas.
Well, that's exactly what one Harrison, Tennessee man is able to do.
The only catch is that it's on his bike.
Jerry Newell has built himself a bike with a motor that he rides every day.
He claims that it gets 128 miles on a gallon of gas, with speed up to 30 miles per hour.
Newell built the bike over a three month span and says two things drove him to doing the research and building his "Jerry" bike...his health and gas prices.
Newell says that he is working out the kinks in the bike and then plans to have these "Jerry" bikes for sale in a few months.
There's already a waiting list of people willing to buy them from Newell.