New cars guzzle more gas than predicted

reply to post by metaldemon2000


Of course they are dyno tested. And they are not even dyno tested to wheel power and mileage either. Only the engine is dyno tested in the auto industry. Dyno stesting is not as accurate as a road type "dyno". The only dyno that even comes close to putting down real numbers is the Mustang dyno. Still the auto industry does not do an accurate reading. There are other reasons as well. In some cases they under estimate HP so that they can get past regulations, in other cases they over estimate it as a selling point.

But another problem I see in the story is the budgeting the woman did to start with.

As for the salesmen knowing the numbers are wrong, that is doubtful. Most barely know which side of the car the fuel door is located on. For the most part even half of the techs working at the dealerships any more are lacking in basic knowledge of how their products work. If you find a good tech at a dealership, you will be lucky if they stay for very long. The sale people though do not know squat about the products they sell. The average person that has researched a car before going to the lot is likely to know more about the car than the salesman.

Raist

reply to post by spyder550


I'm asking for a fuel consumption by rpm for a given vehicle in its sales configuration.

That would already include for that vehicles weight, aero...pretty much everything except what you put in it.

I should have been clearer, but I assumed that since the current testing occurs on the actual vehicle being sold that revised testing would do the same.

reply to post by peck420


Fuel consumption by rpm wouldn't account for aerodynamics. Or for the amount of torque. Being used when say driving up a hill.

reply to post by metaldemon2000


You can derive that information from known information about the car.

So why would I want them to include information that they already include?

I want them to include the numbers that I can't get unless I plug into a computer and monitor the fuel flow myself...which is kind of hard to do until after you buy the car.

I have a hard time taking any of this seriously. people want fuel economy,
while they wait 10 min every morning in tim-hortons drive through , with the
air on. sitting in 6-way leather power seats, fiddling with the dual-automatic
climate control. with all-wheel drive that was never needed in that teritory
untill the last 5-8 years. oh ya , can't forget the 100lbs 18-inch alloy wheels and
low profile tires. gotta have that!
$1.20 a litre for gas, how much is that coffee ? 3-4 a day

reply to post by tothetenthpower


So very true.

If you aren't diligent with maintenance, then you probably won't get the maximum mpg promised. I would probably do so if I bought a newer vehicle because gas mileage is a concern, even if I don't commute much or anything.

One thing many can do that will help with your MPG is to not only do regular maintenance but also find a tuner nearby and have them tune your car for optimal mileage. It might cost a bit upfront but in the long run of owning the car it will help. Note though that if you do this and the dealership catches it, it can void your warranty. That is debatable though as really they have to prove any modification you have done was the cause of the damage.

If you are looking for a cheaper fuel do not go for an E85 swap. E85 will help you get more power and is normally cheaper at the pump but you will not see the mileage with E85 that you will with normal fuels.

Raist

Originally posted by C0bzz
reply to post by JIMC5499

 

Nonsense. By which means do emission control means dramatically reduce the thermo-dynamic efficiency of a vehicle?

My first Kawasaki ZX10R had fuel vapours from the tank routed into the airbox, as with crank vapour (oil) which is really not good for clean burning. There is a oxygen injecting system to avoid unburnt petrol hitting the catalytic convertors (which damages them), it causes combustion before it reaches the convertor. The catalytic converters hinder exhaust flow and thus combustion efficiency. There are exhaust flaps which introduce even more back pressure. Exhaust systems can also be of too long length or with too many bends in order to conveniently mount a silencer. Replacing silencers and tuning is usually good for a few % increase on most engines. Not on very well designed exhausts though

With the zx10r, after modification to race spec, all emissions equipment removed, with top end modifications like cams/gasket/valve springs, full exhaust, ecu + multi gas map, it was a much smoother, happier engine. Lower idle, less fuel (when casually riding), smoother and greater response, also cleaner. You can measure the difference between each engine configuration the good multi gas dyno systems, surprise surprise it's the race tuned one which is cleaner. Cleaner means it burns more completely, more efficiently. More power. It's as simple as that!

All in all, standing behind a cat equipped, oil vapor burning vehicle is much more nauseous than standing behind a fully de-emissioned, multi gas dyno analyzed, race tuned and modified engine. No comparison. It doesn't make your eyes water.

Originally posted by C0bzz
reply to post by JIMC5499

 

Nonsense. By which means do emission control means dramatically reduce the thermo-dynamic efficiency of a vehicle?

Exhaust Gas Re-circulation decreases fuel efficiency, has done since 1973 (76 in some places)

en.wikipedia.org...

^ read the BS in the above wiki article--how can pumping hot exhaust into the inlet manifold be beneficial to the combustion process???

EDIT: I get about 150Km's more on a tank of 98RON (ultimate) than on a tank of 91RON (regular unleaded)--anyone else get a similar increase using higher octane fuels?

reply to post by cartenz


I find some vehicles do, stock high compression bike engines lap it up usually, the extra expense is outweighed by efficiency.

reply to post by GhostR1der


sorry, Im not sure of your response--its my bad.

Are you saying HP engines "lap up" higher octane fuel and perform better, MPG wise? (this I would assume obvious--but Im not an automotive engineer)

or that Exhaust gas re-circulation is "laped up" by HP engines? (this I would be surprised by as I am of the opinion Emission Controls inhibit performance)

sorry for my inability to understand. Much have drunked.

EDIT: since your talking about bikes (which I know very little of) yes, I have seen my friends KTM get more hours (miles/Ks possibly?) on 104RON than what comes out of the pump.

sorry again, Im the one failing to understand here due to "glugg-glugg-glugg"




EDIT AGAIN: No I have never put 104RON in my car (its a falcon ute for you Aussies!) to see if there is an economy increase.

How is it that a teenager can invent something that gets 800+MPG but car companies can only get 40 to 50 MPG.

www.youtube.com...

Originally posted by Grimpachi
How is it that a teenager can invent something that gets 800+MPG but car companies can only get 40 to 50 MPG.

www.youtube.com...

The same oil companies that bought you the gulf war, Acts one and two!.

Look into at what they add to your fuel, and the cancers it causes.

Originally posted by tothetenthpower
reply to post by metaldemon2000

 

There are dozens of factors though that dictate fuel mileage. Not only the vehicle running on the road, but the kind of road, the kind of tire on the vehicle, the weight inside the vehicle, road conditions, temperature etc..

It's almost impossible for the industry to test real life scenarios with vehicles. The reported fuel mileage on any vehicle is clearly the max possible in the best possible conditions.

~Keeper

All true. Also the power to weigh ratio is a major factor. I was an auto mechanic for many years, beginning in the late 1960s. Cars used to get much better mileage. One of my first automobiles was a 1960 Plymouth Valiant with a slant 6 cylinder engine and one bbl carburetor. This car got 60 miles to the gallon every day. Ford Falcons got near 50 miles per gallon. Chevy Novas got 45 miles to the gallon. Gasoline was cheap in those days, $0.35 a gallon when I started driving.
You could fill up an Oldsmobile 25 gallon tank for $12.00.

Since those days, engines have became a lot more efficient, some of today's engines are built on aircraft technology. Car bodies are now unit bodied, and light. There is a great deal of plastic in new cars, that too is lighter than cloths and woven carpets. Some cars have fibreglass body panels. Today's tires are much better, better design, and wear liveability. It could be said that care are better today in nearly every way, right?

And yet vehicles now get worse mileage that those old cars did.

The only way I could ever explain this it, it is in fact a Conspiracy against the American consumer. It is Big Oil, and Big Banks that is keeping cheap running, clean burning cars out of our hands, and off our roads.

Can anyone refute this?

Originally posted by autowrench
Can anyone refute this?

Yes.

Cars of today have much more than cars from that era.

Compare the weights:

1960 Ford Falcon (2 door sedan): 2,259 lbs! They may have been bigger, but most of it was empty space.

1985 Monte Carlo (2 door sedan): 3,239 lbs

2010 Altima Coups (2 door sedan): 3,365 lbs

All three were chosen because they are mid size, 2 door sedans of their times.

A great deal of that weight is safety systems, followed by creature comforts...who new that heated and cooled seats makes your car go slower?