Hypermiling : How to decease fuel consumption

[Lead Head]

Originally Posted by screwballl

Take a simple smaller/midsize truck with a 4 cylinder engine from the late 1980s with its fuel injection and only a catalytic converter, it likely saw around 30-35mpg. Add in the O2 sensor and that drops to 28-30. Add the AIR pump which increases the air mixture to force it to run leaner which is fine on non-computerized cars (1-2mpg drop) but as soon as you add in the computer, that sees a lean running condition and forces the system to add more fuel and that drops it to 23-25mpg.

Your logic is very very flawed here, first of all, at minimum, fuel injection requires an O2 sensor, the O2 sensor is not for emissions, its for the fuel injection system to even function properly. It measures the amount of oxygen in the exhaust gasses, and from there, the computer calculates the Air/Fuel ratio, and adjusts accordingly. If anything, you would get worse mileage without an O2 sensor, as without an O2 sensor, usually the computers will use pre caclulated data, and cause the engine to run rich.

The smog pumps do not cause the fuel mixture to lean out, it pumps air in AFTER the O2 sensor(s) right into the catalytic converter(s), it was really only needed with carb'd cars because they usally always ran slightly rich, it was to assist the converter in burning the hydrocarbons (unburned fuel).

Almost every car, vehicle, truck since 1996(when OBDII was intruduced, along with more modern fuel injection) does not have a smog/air pump.

My truck, a 1987 Ford Ranger XLT, 2.9L V6 EFI, will be lucky to get 22 MPG, and also a Mazda B2200 has about 67 HP, WAY underpowerd for the size of truck it is powering.

One thing many people fail to acknowledge about new cars vs. old cars is the HP of the engine, and weight of the vehicle. Cars now are heavier then ever, easily 4500 lbs for a luxury sedan, causing horrible city mileage (but decent highway), and HP of engines is now higher then ever. Take a mid 70s, early 80s Ford 351/5.8L V8, on a good day, a truck its powering would be lucky to get around 11MPG City, 14 highway, and the engine would barely put out 170HP.

Now take the 2009 Dodge RAM 1500, 5.7L V8, 380HP, and its expected to get around 14-15 city, and 21-22 MPG highway, which is incredible for a full sized pickup.

THe main impact of mileage is bio-fuels, especially fuels like E10, that basically every one has now, that impacts mileage 5-8&

[Capper]

They recently did a big thing on the drivers here (worst I've seen outside of SoCal).....they watched bad drivers, then pulled them over and asked them what they were thinking, and they all basically said they knew they were unsafe, but didn't care.

[PTRMAN]

That is why I drive a huge, old 4WD pickup truck. Helps protect me and my family from all the idiots out there. My wife drives an Accura SUV with full curtain airbags, but I feel much better being taller and bigger than a lot of what is on the road.

[screwballl]

very true... if you look at the sheer number of parts on todays cars, they all need manufacturing facilities... and to make 1000 cars worth in the 60s put out half as much pollution as it does todays 1000 cars. I wish I had the links (multiple sites) with the actual numbers... I will try to find it for everyone...

[Tech Geek Deluxe]

Originally Posted by PTRMAN

That is why I drive a huge, old 4WD pickup truck....

True pickups MUST be able to see over the top of minivans or they simply aren't a true truck.

[screwballl]

agreed TGD

[Zambini]

Originally Posted by Capper

They recently did a big thing on the drivers here (worst I've seen outside of SoCal).....they watched bad drivers, then pulled them over and asked them what they were thinking, and they all basically said they knew they were unsafe, but didn't care.

Same reason 15 MPG has been "acceptable" for the past decade. People just need their bigass car, even though they don't actually have any need for it (with the exception of construction/manual labor/worker/jobs of the like)

[Quakindude]

That's my big ass truck. I can see over most vehicles with it and feels very sturdy. I get about 14MPG in city driving with a 5.9L, 360CI engine and 4WD. I have a boat, so the truck is needed. I also like to go to otherwise inaccessible places. I haul my trailer with mower and stuff on it to cut my mother's grass. After the tornado, it hauled a lot of construction materials to the house. And it's my daily transportation. Not to mention, since I'm not always up for riding my bike 200 miles, I'll use my trailer to haul my bike down to Florida for rides down there.

A truck has many uses for the non-construction worker/laborer type. Just because I'm not a plumber or framer doesn't mean I can't justify owning a truck.

[drew and not u]

Exactly. You can't do this with a Honda:

(7.5 MPG fully loaded @ 25k lbs)

[Lead Head]

Originally Posted by drew and not u

Exactly. You can't do this with a Honda:

(7.5 MPG fully loaded @ 25k lbs)

Come on, you and dad both know if that DPF were to just "fall off", that number would be quite a bit
higher

Nice RAM quakin, I love how the 94-02 rams look