Where Did 84 Mpg Come From?

[goofyone]

I don't know the answer to the OP's question, but if I had to make an educated guess. I would say that since the original engine came from a Geo Metro, and the 1995 Metro 3cyl manual engine got 37 City, 44 Highway, and we've all heard Mr. Elio say (paraphrasing) "...at highway speeds half the power is going to pushing air, Elio is half the width, so twice the MPG" So, using the original engine specs and ignoring power to weight ratios, 1/2 the size of the original car size would give us an estimated 74 city, 88 highway. So it's pretty easy to gauge where the number might have come from. Factor in how much less air the Elio pushes vs the '95 metro, calculate weight differences, and knowing the original engine specs/economy you can extrapolate an estimated MPG range for the prototype.

Again, not 100%, but that's how I would do it during original concept/design and bench-marking.


Some things I noticed while looking at the P4 that could be done to increase MPG. The fenders are fairly blunt, whereas not a wall , they are not as streamlined as they could be. A simple center-line ridge, reducing the head wind facing surface will decrease wind resistance and increase slipperiness. Also, simply reducing the width of the rear tire will reduces ground friction on the drag wheel as well as allow the rear to be further tapered (even if only that the bottom) this will reduce rear turbulence and eddies that cause rear drag as the air leaves the vehicle surface. There has been talk about the grill size being reduced. And I do fully stand by the addition of a small turbo, increasing power to weight increases efficiency. Too much gas is wasted during the "getting up to cruising speed" portion of highway travel. Since turbo's only really add performance under 80-100% throttle, this is perfect for increasing power to get up to speed without struggling and sucking down gas.

Also, to increase city MPG and appeal to a larger market (still don't see this as a city car like the prius) How hard would it be to add one of those "engine off when the car is stopped" options? I haven't researched what goes into those, but I'm pretty sure it's nothing extra other than programming. That would greatly increase the MPG for the city specs AND increase market desirability.

Anyway, just my 200 cents.

Great post!

Paul Elio has actually stated how they came up with the 84 mpg goal. 84 mpg it is 3x the current average highway fuel economy of 28 mpg. Something tells me that logic along the lines of what you pointed out is what lead them to believe this was an entirely possible number to achieve from such a vehicle and probably got this project rolling back in 2008.

We will see what changes they make to the front end to help achieve their aerodynamic numbers as they have been refining the shape in each prototype to make things more efficient so it is entirely possible some changes along the lines of what you mentioned may be incorporated into the P5 design.

Paul Elio has mentioned hat IAV was working on a turbo for this motor so I would expect this to eventually become an option for those who want more power. I can see this being a very popular option for people looking for a very inexpensive car with a very good power to weight ratio making for some extra fun times. I doubt the turbo would be standard item purely do to the extra cost of the turbo and EM trying to keep this car as inexpensive as possible.

We actually already have an ongoing discussion on start/stop systems. There are several ways of doing it but some current vehicles have indeed achieved this only via engine ECU programming. I don't know if Elio Motors will have the time and money to develop this technology before production begins however I would also like to see it eventually as it would help increase that city mileage number.

http://www.elioowners.com/threads/start-stop-system.812/

 

[Jim H]

Goofyone, Congratulations on officially becoming an Elio Addict. Well done and thanks for all your dedication to making this a great forum!!!!!!!

 

[zelio]

Goofyone, Congratulations on officially becoming an Elio Addict. Well done and thanks for all your dedication to making this a great forum!!!!!!!

Congratulations are definitely in order, Goofyone. You are the best! Thank you for all you do for the forum and for all the information you provide. I'm very glad you are one of us! :-) Z

 

[pj rogers]

You can add Stop, stop technology after the sale, have seen it advertised for $169.95...plus install.
Goofy, you do a good job, here is a test.
How can the elio owners send the C.A.F.E. people a message bring the autocycle (elio) into the credit picture without making it a car.. We could send in thousands of e-mail, texts, letters to them, and get us into the program, or at least make them aware of us. We the credit, we all get our elios...might be worth a shot..get us a contact.
(see automotive news, april 9th 2013)

 

[ArthurKent]

As a note, govt highway economy test cycles are rough estimates, considering the fact that they are
carried out in a room, and calculate air resistance factors, etc. And their "highway test" is nothing lke
a cruise down the Interstates - top speed never exceeds 51MPH, as I recall, and was at that speed
a small portion of the test loop. It doesn't even remotely resemble typical Interstate travel.
Significantly, the test also does not involve the use of A/C or heating. Heating KILLS the mileage of
electric cars, but extracts virtually no penalty from a gas powered vehicle, like the Elio - the only
energy required, if any, is running the fan to ditribute the engine's heat.
My experience is that I could never discern what effect A /C plays in my car's gas mileage.
ON a long Interstate trip, driven with and without A/C, I couldn't really detect any difference, although there
must be some, assuming that the car had the windows wound up in both cases.
I also once owned a Pontiac Fiero, which, like the Elio, had a half sized interior, and used the A/C system
from a Pontiac compact sedan. You could store sides of beef in that Fiero's interior. It had the most effective
A/C of any car I've have ever driven or ridden in. Pontiac could have used a compressor half the size of the
one that ended up in the car.Of course, like engine size, simply having a larger compressor has little effect
on the amount of energy required for cooling (and effect on mileage) - it's all about how often it needs
to run to keep the car cool inside.

 

[goofyone]

You can add Stop, stop technology after the sale, have seen it advertised for $169.95...plus install.
Goofy, you do a good job, here is a test.
How can the elio owners send the C.A.F.E. people a message bring the autocycle (elio) into the credit picture without making it a car.. We could send in thousands of e-mail, texts, letters to them, and get us into the program, or at least make them aware of us. We the credit, we all get our elios...might be worth a shot..get us a contact.
(see automotive news, april 9th 2013)

This is a great question. I will contact Joel Sheltrown, Elio VP of Government Affairs, and see how we can help push this along.

 

[goofyone]

As a note, govt highway economy test cycles are rough estimates, considering the fact that they are
carried out in a room, and calculate air resistance factors, etc. And their "highway test" is nothing lke
a cruise down the Interstates - top speed never exceeds 51MPH, as I recall, and was at that speed
a small portion of the test loop. It doesn't even remotely resemble typical Interstate travel.
Significantly, the test also does not involve the use of A/C or heating. Heating KILLS the mileage of
electric cars, but extracts virtually no penalty from a gas powered vehicle, like the Elio - the only
energy required, if any, is running the fan to ditribute the engine's heat.
My experience is that I could never discern what effect A /C plays in my car's gas mileage.
ON a long Interstate trip, driven with and without A/C, I couldn't really detect any difference, although there
must be some, assuming that the car had the windows wound up in both cases.
I also once owned a Pontiac Fiero, which, like the Elio, had a half sized interior, and used the A/C system
from a Pontiac compact sedan. You could store sides of beef in that Fiero's interior. It had the most effective
A/C of any car I've have ever driven or ridden in. Pontiac could have used a compressor half the size of the
one that ended up in the car.Of course, like engine size, simply having a larger compressor has little effect
on the amount of energy required for cooling (and effect on mileage) - it's all about how often it needs
to run to keep the car cool inside.

The EPA fuel economy testing is far from perfect however it has been improved over the years. Since the 2008 model year the EPA has included testing with the AC running and some correction for temperature variations.

http://www.fueleconomy.gov/feg/ratings2008.shtml

http://www.fueleconomy.gov/feg/fe_test_schedules.shtml

 

[Paladin4Elio]

By the numbers 3 X 27 is 84.1. Paul Elio said he wanted the Elio to get 3 times the mileage of the average car in this country.

Is that avg of 27 mpg for hwy, city, or combined mpg?

Comparing it to 84 mpg hwy estimate for the Elio only makes sense if it too is for hwy.

 

[karl]

84 is the estimated hwy number

 

[Paladin4Elio]

84 is the estimated hwy number

I know that. I asked whether the 27 mpg (that the 84 mpg is 3x of), is also hwy or city or combined.