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Old 01-05-2011, 08:52 PM   #9 (permalink)
IamIan
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Quote:
Originally Posted by PaleMelanesian View Post
Since this was an "ultimate range challenge" and therefore also an ultimate mpg challenge, you can be sure the speeds were slower. However, the quote above should give you the information you really want. If you had this car and cruised at 65 mph, you could expect low 50's mpg, or crossing the country in three tanks of gas.
Unfortunately that quote does not give me the information I am looking for.

From what I can tell that quote was not from how he drove this trip.

On the CleanMPG thread in the very beginning of the effort Post #17 Wayne responds to a question about what he expected for average speeds ... and at that point in the beginning his response was:

Quote:
Probably 55 +/- on the mains while DWL and evoking ICE -Off glides wherever they can be completed. 50 + on the secondary’s if they are 55 mph PSL’s and nobody is behind.
That does not read like he was intending to cruse at 65 MPH to me.

Further considering the given start date of 12-25-10 , and the end date of 1-1-11 ... it seems like he only traveled about ~300 Miles per day ... I don't know how many hours he spent driving the total distance ... but if he was driving for just 8 hours out of every 24 hour period ... that would give him an average of around ~38 MPH for the trip.

He posted a final MPG rating of about ~50% above the EPA Highway number.

Given that we know he wasn't coming to a complete stop as often as the EPA Highway cycle test does ... and he pumped up the tire pressure above what the EPA Highway cycle test was ... we would expect to see some improvement above the EPA rating.

To better understand the results we need to know more about the context that gave these results ... and right now the average driving speed I think is the biggest missing piece of information.

- - - - - - - - -

Quote:
Originally Posted by Old Mechanic View Post
Average speed is relevant as Ian has asked. I could get 60 MPG in my automatic Altima at 40 MPH, but I will never drive cross country at 40 MPH.
Agreed.

Quote:
Originally Posted by Old Mechanic View Post
The truly relevant point is Hyundai did their homework and understood the true pathway to efficiency. The better the car is designed the harder it will become to really beat EPA ratings, especially if you are driving the car in a similar fashion.
~90% agree.

My last hold out ~10% would be , three things...

The EPA ratings have never been designed to be the best the vehicle can get ... as such there will always be people who can do better... it is just a standardized test in order to compare vehicles ... it is not about anyone actually getting the EPA numbers ... just which vehicle is more likely to give better MPG to the average driver , in the average real world conditions.

I also do not know of anyone who has ever been able to actually beat the EPA MPG numbers while driving the EPA cycle ... driving in a different context , with different speeds , more or less stops , softer or harder braking , softer or harder accelerations , etc.... when you change the context it is expected to get different results ... sense I don't know of anyone who tries to beat the EPA MPG numbers on the same driving context / conditions the EPA got their MPG numbers ... all other MPG numbers are a different context... at best being able to beat those EPA numbers might indicate your driving method + your driving conditions together were that much better than the EPA driving conditions and drive cycle.

I doubt the road trip was about the tech or the design of the car ... that could have been done ... and the vast majority of it was done over much smaller distances, prior to the road trip ... without spending that much time or gasoline.

Quote:
Originally Posted by Old Mechanic View Post
As the manufacturers study the efforts of those members here and incorporate those into the design of their cars, EVERY driver will benefit from better design.
Agreed ... I look forward to seeing more of it deployed.

Although ... I guess from my point of view any good Automotive Engineer knew allot of if not all of this stuff a very very long time ago ... even if they had other priorities and just didn't choose to include allot of it for one reason or another.
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