Well thats all the little 318 in thetruck has in overdrive, you can only push the peddle so far before it downshifts and buriesthe tach. With O/D off you can just hammer on it, the speedo and the tach will bury themselves together

But really who gives a ****, I really dont like going over 80 mph in my truck anyway

 

+1 TheForces55555

I have the same setup as you, just extended cab.I'm lucky if I do 70 max on the highway and no real need 2 go 80 imho.

 

My truck kicks out of overdrive if I drive slower that 45 or so. You CAN hear the engine having a hard time then.

Most you guys have 4wd's jacked up with larger tires. These all count against you with mpg. If you do any reading whatsoever, you know that the best way to save fuel is to slow down. I have never heard of a truck that could get better mileage at 75 than at 55. It would be cool to see proof of that.

Hankl wrote an mpg article that had professional and regular driversdrive the same car. Some of the pro's got the car up to 30mpg, some of the Joes got as little as 10. With the low restriction cat and Super 44 I can hear the truck and get out of the throttle. At long lights I shift into neutral. I keep 40psi in the tires. I keep it between 55-60.

 

After much reading, it seems there are two ways to get better mileage right off the bat.

Take your foot out of the throttle so much, like Ramaniac said, or just go buy yourself something that burns rice.

Otherwise, work on a new concept to promote better mileage.

One way to do it is by making your own fuel additives. Just add 2-3 oz. Acetone, 2 oz. xylene, and 1 oz of 0W40 fully synthetic motor oil to every 10 gallons of fuel to improve vaporization of fuel in your tank. It will reduce emmisions, and promote better ring seal. Try it, and record your results...

This additive is for Gas engines, for diesel, it's about 3-5 oz. acetone and 1 oz. 0W40 synthetic oil per 10 gallons of fuel.

Nest idea might be to create a vaporiser for you fuel so that the fuel will have a larger surface exposed to air. Hopefully, if conditions permit, this would result in a fog being generated that can be sucked into your engine through a vaccum port. Unlike the spray that is created by injectors which is actually more of a liquid then a vapor which inherently has less surface area exposed to air which is available to burn.

Idea is to send low pressure fuel from a return line, or from a main line under regulated pressure into a perforated tube inside of a cylinder at adjustable quantities by use of a adjustable valve. After the fuel enters the perforated tube, which has tiny holes in it created by drilling used to create a fog sized particle, the fuel enters the main body of the cylinder. Air is then mixed with the fuel particles in the body of the cylinder. The air enters the cylinder through a vent that is regulated using another adjustable valve. And finally after the fuel and air are allowed to mix inside the cylinder, the mixture is allowed to be siphoned out of the cylinder into a regulated line, by use of yet another adjustable valve, and finally into the intake manifold through tapping into a vaccum line somewhere.

This is a concept that I've seen a few variations of. Here are some of them. The first two don't exactly describe how the vaporization occurs, but the third variation I found described how the cold vaporization occured. Unfortunately though, the site that hosted the design is no longer available. However, I've given the design, so now it's up to you guys to work with it if better mileage is even a concern. The remainder of the site that hosted the info is this, http://www.brightgreen.us/ , http://www.brightgreen.us/smartgas/ , http://www.brightgreen.us/lubedev/ , http://www.brightgreen.us/lubedev/articles/ , lots of good info to be found...

http://www.agsint.com/atom3.htm

http://www.fuelconcepts.com/

Next, concept may be by altering the signal created by your O2 sensor in order to trick your PCM into running on lean mixtures when just cruising. If electronics are someone's specialty here, maybe they could make one of these. All of the parts should cost less then $50 to purchase. And if the concern of having a meltdown occurs due to running on lean mixtures of fuel and air, just add water injection. This site covers the whole subject.

http://www.better-mileage.com

http://better-mileage.com/memberadx.html

http://better-mileage.com/water4.html

Then you can always do something else. For example, preheat your fuel. This is something that the http://www.brightgreen.us/install.htm and other sources I've come across have used for gains in mileage, and that's not all.

 

if you want gas mileage, get a neon

 

too much to read, plus the first few posts were calling bs so I stopped wasting my time


Ok for all the idiots that called bs I took my third gen for a 100 mile run at 60 and I got 19mpg, took it for a 100 mile run at 48 and got 24. Yeah I dont work so I dont mind wasting my time.

 

I get 16 mpg at 55 or 65. I live in rural southern AZ. The speed limit is 65 here (mostly). I have driven and checked with several tanks of gas. I don't measure by how much I think I used, I measure by the amount of fuel up-which is the only accurate way to measure.I am a fanatic about finding ways to save fuel and raise mpg, my 2003 Neon gets 36-38 mpg with an auto transmission. I know how to conserve. Maybe 55 works for some people, but for the doubters, I can loudly agree: 55 or 65 makes absolutely no difference. The biggest factor for me is how fast I accelerate to 55 or 65.

ps I have a 98 1500 QC 318 Auto 2 wd

 

It is one thing to speculate on what difference it makes. It is another matter altogether to have your fuel logs in front of you.

 

It's not something cooked up by the whacko's during the gas crisis. It's simply based on Reynold's number which gives a good approximation of the force that resists movement through a liquid and when that force changes from a linear relationship to a square relationship. Very *very* basic fluid mechanics. You take that info along with the efficiency of a vehicle at different speeds (Assuming no wind resistance) and it will give you a curve...the low point of the total curve just happens to be around 55 mph. If you go faster or slower you will start losing efficiency. Same thing happens in airplanes (with a few more variables) and it's how we find out our best glide speeds, best range cruise speeds and best time cruise speeds.

I also did some experiments while I was stationed at Altus and drove back to Tulsa on the weekends (About 300 mi. one way) in my ricer. The roads are pretty much all highway (95% by length) and between gas stations (Where I took measurements, distance verified by GPS accurate to 18 meters) I only saw three stoplights in that 300 mile stretch. Driving speed limits (70mph and 75mph on the pike) the entire way I got around 22 mpg reliably. Changing to a K&N, new plugs/wires, etc and drafting behind semi's pushed my mileage up to about 26 mpg. I started reading on this hypermiling business after listening to a special on NPR with a guy that got over 90mpg out of his hybrid. I employed some of his techniques about avoiding hitting the brakes at all costs (Looking far enough down the road to get off the gas rather than brake off the speed later), religiously driving 55 mph (He actually put a mpg computer on his car and developed a curve that showed his best mileage speed ranges), and accelerating on straightaways or on downhill runs (in bigger theory this shouldn't matter, but due to the design of the engine it does). He also drafted semi's, but it was hard to find semi's driving 55 on the 75mph turnpike. I was able to break the 40 mpg mark regularly and nearly got it up to 50 on one particular drive (Tailwind the entire way). For a 12 year old Honda with 200k that ain't bad at all!

In retrospect, I kind of think I should have driven faster when I had the tailwind and maybe a bit slower with a headwind since the movement through the air mass is the important part. There's still the consideration of the efficiency of the motor and I haven't got one of those fancy little OBDII things that reads out your mpg. It'd be an interesting experiment though.

All in all, if you can make the time to drive a bit slower it actually is cheaper...science says so!

 

I'm going to have to say thatwas actually the best way of stating it I've read thus far.

1.) Every vehicle is not the same.
2.) Every driver doesnt drive their vehicle the same
3.) Something as simple as gearing, motor, transmission, they all change the way your vehicle performs
4.) Using cruise control (if you have it) can help gas mileage ALOT

First off, not every vehicle is built the same, and that is why I believe alot of people disagree with Rammaniac's viewpoint. To a certain extent, he is correct that by lowering your speed, you can improve fuel economy. He's also correct that if you have a 4x4 and a lift or larger tires, your gas mileage will suffer.

What he failed to mention however, was that most vehicles today are being test at higher speeds for wind resistance, thus IMPROVING mpgs at higher speeds. This is to not only improve MPG, but also for other various tests they are studying...

Every single vehicle is different, and like Mudbone stated, the best "speed" for any vehicle, is when you find that sweetspot where the vehicle begins to float. Now for some, that'll be 55....for others, it'll be 59 or 63.... it just depends on your vehicle. My 01 Dakota got better MPG's at 61 then at 55, but it also got crappier mileage at lower speeds because the truck spent too much time building up speed to push it around.

You also have to factor in rolling resistance, aerodynamics, performance upgrades, gearing and tranny performance.....as these are all major factors in improving or damaging your mpgs. Manual trannies used to get better mpgs, but that's not the case entirely anymore. Utilizing cruise control on long straight aways at a certain speed can also improve MPG considerably as the motor doesnt require ashigh an RPM to perform. I use it quite religously, and can see a difference in fuel mileage when I dont.

All in all, the whole 55 mph thing isnt a myth, but its also not 100% accurate either. Essentially what it boils down to is taking the time to learn your vehicle and do some testing. Rammanic did his, and found his to be around 55mph. He shared that info and got slammed for it......however he got very defensive when some people called BS, because of their own experiences. He's right, and some of you are also right....