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micrometer50
07-13-2006, 06:07 PM
I was wondering the other day, does the dramatic increase in gas prices make engine efficiency measures more worth while in the eyes of manufacturers. I'm talking about things like roller cams, anti-friction coatings and the like.
Thanks

Evan
07-13-2006, 06:19 PM
There isn't much to be gained by those means. Lighter vehicles and smaller engines/hybrids are the only current way to make a real difference.

Rich Carlstedt
07-13-2006, 06:42 PM
Well it will make some change in the mechanics of the drive, but probably make a greater change in the operator.
Some of the things that detract from better mileage are:
Heavy cars..look for composite vehicles
Road design...we are fixated on traffic lights and stop signs. they need to go !
and yes, the Europeans are far ahead of us here, with
roundabouts...a plus here is less polution IF YOU are moving
Tire design...look for harder tires and thinner..but safety can restrict this
Engine design..look for a return to air cooled engines,& engine "life' will suffer
Water Injection.. repealed from the past, as it slows combustion for more MPG
Computer controlled throttles... dial the mileage you want.don't expect speed!

Rich

bob308
07-13-2006, 07:25 PM
well i live in pa. where round abouts are common. people can not get the idea on how they work. you are always taking your life in your hands when you have to go through one.

DancingBear
07-13-2006, 09:37 PM
well i live in pa. where round abouts are common. people can not get the idea on how they work. you are always taking your life in your hands when you have to go through one.

They're getting popular in Indy too, with similar results. I deal with one twice daily and I've noticed there's a real 'tyranny of the more-travelled' that goes on. If there's a lot of traffic on the east-west street and not so much on the north-south, the guy going south could be waiting awhile. I suppose the overall mileage for all cars would be better, but YOURS might not be, compared to a 4-way stop, which is biased toward the less-travelled direction.

As to the engine question, I'm not much of an engine guy, but I suspect a lot of the friction-reducing strategies used in racing (coatings, spiffy bearings everywhere, etc.) wouldn't translate well to ordinary cars due to maintenance requirements. The initial price difference vs. an ordinary engine could really hamper its popularity too. Just my $0.02.

Walt

Al Messer
07-13-2006, 09:47 PM
All I can see in the foreseeable future is a thinner wallet.

Evan
07-13-2006, 09:56 PM
On our recent trip to Alberta I drove our PT Cruiser. It isn't the best car for gas mileage as it is quite heavy, something I like because of the stability and safety that gives. However, I decided to try something before heading back from Hinton to home.

Our PT is equipped with a factory installed roof rack. The factory recommends that when not in use both bars be slid together toward the very back of the tracks. This seems reasonable and it looks a lot like a spoiler.

Drawing on my experience with aircraft and the use of spoilers and turbulators it occured to me that it might be an advantage to reposition the roof rack a little further forward on the roof. In the pic you can see that I moved it about eight inches forward from the rearmost position on the tracks.

http://vts.bc.ca/pics/ptc1.jpg

My thinking was that this might reenergize the air boundary layer and keep it attached further down the curved back of the car, thus reducing drag. Similar methods are used on aircraft to keep the airflow attached on the rear portion of the wing, especially over the flaps. Small vertical turbulator fences are used on the inner third of the wing on the Cessna Citation Business jet for exactly this reason.

We then drove back the 650 or so kilometers to Williams Lake. I was astounded to find that my gas mileage increased a solid eight to ten percent on the hiway drive home. I am also finding a smaller but noticable increase in mileage in regular around town and work commuting which never exceeds 80kmh.

Mad Scientist
07-14-2006, 12:53 AM
Some thoughts on relieving gas pains. For about the past year I have been adding acetone to my gas every time I fill up. (2 oz. for every 10 gallon of gas.) This has resulted in an extra mile per gallon. While not earth shaking at least it is a step in the right direction.

Meanwhile in my area we have a big push going on to get people to use the new E85. This is a blend of 85% alcohol and 15% gas. It is being sold as homegrown cheap alternative to regular gas and it IS a few cents per gallon cheaper then regular gas. However what the average Joe six pack is slowly coming to realize is that his mileage is drastically reduced and as such that he must now burn more E85 fuel to go the same distance. The reality being he is now has to spend more money to use a cheaper fuel. :(

The following web site is by a guy who has been experimenting for about the last 50 years with different methods to get better mileage. There are a number of looong articles, some of which are a bit redundant, still though I found much detailed information on the things that he has done and what actually works. He explains why you should use acetone and how it works.

http://www.lubedev.com/smartgas/

Evan
07-14-2006, 01:25 AM
He explains why you should use acetone and how it works.

No he doesn't. He gives an explanation that may sound reasonable but has no basis in science.

In fact, his explanation doesn't even sound reasonable. It sounds like the bunk that it is.


Acetone, xylene, neopentane and other methyl carrying hydrocarbons are the slowest burning chemicals known to man. These survive the heat of combustion for a very long time although they vaporize readily. Still they burn slowly. By their fierce vibrations, they break apart the massive fuel fragments that surround them. Thus they encourage great vaporization.

gmatov
07-14-2006, 02:39 AM
Never in the next 27 years, at least, will the price of gasoline deter you from driving all you want.

I have read of people buying "Hummers" who said they would make, "Maybe, one less trip to McDonald's per week".

Idjits who spend 40 to 60 thou per vehicle eat at McD's, but will eat there less often.

I guess there ARE some for whom the vehicle is their entry into the neigborhood they want to be in. Kissass neigborhoods, I guess you could call them. Any of you have any idea how goddamned restrictive some of them town house agreements can be? Pretty goddamned restrictive, and the courts have agreed to them..

Most of you must not be there, as you are trying to set up a little, or a large, shop.

If you were in some places, zoning would tell you you gotta move.

My own kid, on our local Planning Committee, told me this evening I could not build my secondary garage where I want to build it because it is a little forward of my house, proper, must be alongside or behind the house.

I think I am gonna build it and screw 'em. WAY too much stuff in my main garage, can't even find the stuff I am trying to get rid of here.

Cheers,

George

Weston Bye
07-14-2006, 05:40 AM
I bought a used '01 Stratus a year ago. Not long after I had outlived the dealer warranty the engine developed what I thought was valve noise. Turned out to be piston slap, a common problem with these cars, according to my mechanic. The 2.7L V6 would eventually require a short block. He said to drive it until it failed. The noise was most evident above 3000 RPM and almost nonexistant below, with a little tick at idle. I resolved to keep the RPM below 3000 and drive it as long as I can. THe result of my engine-conserving strategy is that the car gets 29-30 MPG, most of my driving being expressway miles. This is better than the 27-28 MPG that I get with my PT cruiser, and is a more comfortable ride. I have to plan ahead on the on-ramps to avoid the need for sudden acceleration.

Wes

Rustybolt
07-14-2006, 09:16 AM
I was wondering the other day, does the dramatic increase in gas prices make engine efficiency measures more worth while in the eyes of manufacturers.

Not until they become more worthwhile in the eyes of the consumer. You can make the most reliable, environmentaly sound, fuel efficient automobile in the world , but if the market doesn't want it, it won't sell. Since markets drive everything it's a safe bet that those manufacturers with the most fuel efficient cars will sell the most. If fuel ever goes below $2.50 a gallon Hummers will once again be in vogue. Or if they make a hummer that gets 30 miles to the gallon.

Mad Scientist
07-14-2006, 10:06 AM
He explains why you should use acetone and how it works.

No he doesn't. He gives an explanation that may sound reasonable but has no basis in science.
In fact, his explanation doesn't even sound reasonable. It sounds like the bunk that it is.

EVEN:
OK if you don’t like his explanation of how it works, and I certainly don’t except everything he says, “still” how do you explain the fact that it works? Because it DOE’S work. I know a number of people that are using it and while results vary, all are getting better mileage.

Evan
07-14-2006, 10:42 AM
There is not one study conducted under controlled conditions that shows any improvement caused by using acetone. Not one. There is also no scientific reason for it to work. There is no room to improve the combustion efficiency of modern gasoline engines since they already combust the fuel at around 98 to 99 percent efficiency.

It doesn't work and can't work.

IOWOLF
07-14-2006, 02:01 PM
Let me think here,If you put 10% of anything into a gallon of gas will it not increase the volume of the gallon. there fore increase the mileage because you are now useing more fuel diluted as it is.

Just a thought.

Ries
07-14-2006, 02:12 PM
We already have the technology to increase mileage- smaller cars and smaller engines.
I was in europe a few years ago, and rented a station wagon for a month- it was a Peugeot Diesel, about the size of a Subaru- it seated 4 adults comfortably, and got something between 40 and 50 miles per gallon.
And on the tollroads I drove it at 90mph or so quite easily.
Still got passed by Mercedes, Audi's and BMW's like I was standing still, of course.

But the trick was- smaller car, small (about 2 liter) 4 cylinder engine, diesel.

Tradeoffs- no Sofa sized seating, no 8 foot above the road view from on high, and fewer horsepower meant slower acceleration- it did have a turbo diesel, so it wasnt THAT slow.

This was at least a 5 to 8 year old design- the japanese and europeans have even better stuff now.
But we dont want it because we like big cars.
Plus the europeans have looser rules about the sulfur content and particulate emissions of diesel, but that is changing- within a year or so we should be seeing more 4 cylinder diesels here that meet our emissions standards and still give 40+mpg.

Spin Doctor
07-14-2006, 02:39 PM
What surprises me is that no one is selling a diesel hybrid -yet. Just about all of the friction reducing tricks that one could use in a mass produced engine are being used already. Roller rockers and tappets, molycoat on pistons ect. If we see a breakthrough in battery technology we may see hybrids in which the gas/diesel engine is the suplimentary power source. Of course a real breakthrough in battery tech would mean fast recharges, comparable range and the ability to maintain the power level while in storage (and then we would be complaining about the price of "electrons" at the plug) . But for now, drive conservatively, keep your tires at proper inflation pressure and cut out those extra trips.

Evan
07-14-2006, 03:31 PM
Still got passed by Mercedes
Yes, of course. Mercedes drivers are required to sign a secret agreement wherein they promise to never allow an inferior make of automobile to pass them on the Autobahn. If passed because they are daydreaming or something then they must make all possible efforts to remedy the mistake by passing at the highest possible velocity as soon as they can.

Tin Falcon
07-14-2006, 03:58 PM
Meanwhile in my area we have a big push going on to get people to use the new E85. This is a blend of 85% alcohol and 15% gas. It is being sold as homegrown cheap alternative to regular gas and it IS a few cents per gallon cheaper then regular gas. However what the average Joe six pack is slowly coming to realize is that his mileage is drastically reduced and as such that he must now burn more E85 fuel to go the same distance. The reality being he is now has to spend more money to use a cheaper fuel. :(

From http://www.e85fuel.com/e85101/faqs/e85.php
"What is E85?

E85 is the term for motor fuel blends of 85 percent ethanol and just 15 percent gasoline. E85 is an alternative fuel as defined by the U.S. Department of Energy. Besides its superior performance characteristics, ethanol burns cleaner than gasoline; it is a completely renewable, domestic, environmentally friendly fuel that enhances the nation's economy and energy independence. "

E-85 requires a specialy designed engine/ vehicle.
Many states have switched to E-10 which will burn in virualy any vehicle designed for gasoline. NJ no longer sells gas with MTBE all refineries are now producing E-10.

Fuel comparisons
from National Association of Fleet Administrators, Inc.
100 Wood Avenue South, Suite 310, Iselin, NJ 08830
http://www.nafa.org/Content/NavigationMenu/Resource_Center/Alternative_Fuels/Energy_Equivalents/Energy_Equivalents.htm

Fuel Type Unit of Measure BTUs Per Unit Gallon Equivalent

Gasoline, regular unleaded, (typical) gallon 114,100 1.00 gallon

Gasoline, RFG, (10% MBTE) gallon 112,000 1.02 gallons

Diesel, (typical) gallon 129,800 0.88 gallons

Liquid natural gas (LNG), (typical) gallon 75,000 1.52 gallons

Compressed natural gas (CNG), (typical) cubic foot 900 126.67 cu. ft.

Liquefied petroleum gas (LPG or propane) gallon 84,300 1.35 gallons

Methanol (M-100) gallon 56,800 2.01 gallons

Methanol (M-85) gallon 65,400 1.74 gallons

Ethanol (E-100) gallon 76,100 1.50 gallons

Ethanol (E-85) gallon 81,800 1.40 gallons

Bio Diesel (B-20) gallon 129,500 0.88 gallons

Electricity Kilowatt hour 3,400 33.53 kwhrs

Regards
Tin

John Stevenson
07-14-2006, 04:09 PM
We already have the technology to increase mileage- smaller cars and smaller engines.
I was in europe a few years ago, and rented a station wagon for a month- it was a Peugeot Diesel, about the size of a Subaru- it seated 4 adults comfortably, and got something between 40 and 50 miles per gallon.
And on the tollroads I drove it at 90mph or so quite easily.
Still got passed by Mercedes, Audi's and BMW's like I was standing still, of course.

But the trick was- smaller car, small (about 2 liter) 4 cylinder engine, diesel.


Ries,
That's what both Gert and myself run.
Gert runs a 1.9 litre turbo estate car, gets about 45mpg.
I run a 3 ton van with 2.5 straight engine, that gets about 30 to 33 and it's usually 1/2 loaded at all times, [ ran around for 3 months with a Bridgy in the back ! ]

We have had five vehicles now, all with Peugeot diesels and wouldn't change onto any other.

They seem to be the most sucessful small diesel out there.
I don't rate the Jap diesels as they are always changing the design and after two years you can't get spares, they want you to trade in.

.

Mad Scientist
07-14-2006, 04:43 PM
It doesn't work and can't work.

OK so why does it? A friend of mine has been using it in his wife’s car. She only uses this car to drive back and forth to work, same route every day, same time of day, same amount of traffic, on Fridays they use her car to go get grocery’s and they also stop to fill up the tank. Previously it would require around 10 gallons to will up, since using acetone, for about a year, it now requires only around 8 gallons. So what is going on?

Evan
07-14-2006, 04:47 PM
Driving habits have changed. If somebody is putting acetone in their gas they obviously want to improve gas mileage. They have a vested interest (subconciously) in it working and are very likely to change how they drive. It doesn't take much to make a big difference in gas mileage. Accelerate just a bit slower, coast a bit more, drive a little slower and it all adds up.

There is also the fact that a bit of acetone in the fuel is a good injector cleaner but that only needs to be done once in a while.

Fasttrack
07-14-2006, 11:41 PM
Let us not forget that acetone *will*, in fact, raise vapor pressure of gasoline - but not by the means of "vibration". Rather it is due to colligative properties. At, say 104 degrees fahrenheit it will raise the vapor pressure of gasoline some considerable amount. Even with a relatively low mole fraction, with a vapor pressure of 400 mmHg (again at 104) will make a considerable change. Also the extra oxygen atom in the acetone allows for a more complete burn with less CO emission. Incidently this is why nitrous oxide is used, and why nitromethane and methanol is also used as race fuels. The added bound oxygen atoms allows a greater volume of fuel in the cylinder during combustion. Of course, in this case, we dont want more volume, just a more complete oxidation (although this effect is negligible at best with such a small amount of acetone) and the increased vapor pressure could result in a fuel air mixture that is better atomized during injection. Thus you would expierence more "bang for your buck". It would develop a *very* slight amount of more hp. Again this effect should be neglible, but this combined with the very noticable difference of driving practice, as Evan pointed out, is probably the cause for your increased gas mileage. Still i'm not sold on using acetone...

Rich Carlstedt
07-15-2006, 12:35 AM
All I can say, After driving in England many times, is my hat is off to Sir John and his fellow countrymen.
They know how to drive properly compared to many Americans.
Cell phones may have changed that now, but up to 10 years ago, when they drove, they drove and did not polish fingernails or fiddle with the 200 watt amp. ( maybe stick shifts and manual steering does it )
I mentioned roundabouts earlier , because in England, they make them proper. Here in Wisconsin, they make them about 60 feet across which is absolutely rediculous. it's the same as an "All Stop"
We should be able to go through at 40 MPH as they do in the rest of the world ( 100 yards diameter) , and the driving test should be --Swindon UK.

Rich
Green Bay Wisconsin

SJorgensen
07-15-2006, 01:05 AM
I haven't done any calculations on this idea but it is about stored energy. Lets say you had a pressure vessel that could be pumped up during braking. Then when the light turns green the pressure gets released back into the cylinders to propel you back up to 30 mph. In city driving it is the wasted energy of stop-and-go driving that consumes huge amounts of energy. An intelligent traffic management system or a system such as this or regeneration like the hybrids do during braking will cost the energy industry billions! But of course they will just shift the price again because they control all the market variables on the supply side. They just create a war or shut down some capacity here and there. It's taught at Harvard and Yale.

John Stevenson
07-15-2006, 04:57 AM
We can't have 100 yard islands here.
That two industrial estates or 75 houses gone :D:D

.

cybor462
07-15-2006, 06:32 PM
I have tested! I just came back from a small get away. I rented a 2006 Ford Taurus 6 banger w/air It was a surprisingly big car. It has the est gas mileage readout which I watched the whole trip. I filled up in PA where we do not have ethanol in our gas (yet) and I got 31 mpg running mainly highway with the air on all the time. We drove to CT so I was unable to use cruise going thru NY and Jersey (man those guys are nutz!) There was two full size adults and one full size young adult (we like everything full size). We used 10 gals. to get there. Roughly 300+ miles. Ok we drove around a lot while there. I did not have to fill the tank again until we left for home. Guess what CT has E10 so now we got a full tank as the tank was on fumes when I filled it. We headed home with a full tank of E10 running the air the whole trip and again no cruise. Outside air temp was the same and go figure it was raining when we left and again when we came home. We got home and used 14.5 gallons of gas. Yes it is proven E10 is less efficient as far as mpg. You have to do it to see it!
I can't say why and I agree driving matters but I would say this was a decent test as the parameters were all but identical except for the fuel used. And that E10 cost us .40 more per gallon.:eek: