is driving over 60mph really this inefficient

conjur

No Lifer
Jun 7, 2001
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Look for a graph showing how drag increases with speed and I think you'll have a good answer.
 

Zenmervolt

Elite member
Oct 22, 2000
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Varies by car. Largely a function of gearing. The graph is wrong though. I have yet to have a car that did not peak in fuel mileage between 35 and 45 mph. 55mph is not the peak of efficiency, it's just as low as they could make it without having the country rise up with torches and pitchforks.

My Lincoln is rated at 26 highway. I get 26mpg cruising at a steady 80mph on the interstate. Have gotten 28 at a steady 65.

ZV
 

Vette73

Lifer
Jul 5, 2000
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Originally posted by: conjur
Look for a graph showing how drag increases with speed and I think you'll have a good answer.



That and you run out of gearing. Cars are made to run more from the line to 60ish. Mind you a corvette with a 6speed manual goes to sleep in 6th, but I am speaking in MOST type cars.
 

osiris3mc

Golden Member
Oct 23, 2001
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Originally posted by: Marlin1975
Originally posted by: conjur
Look for a graph showing how drag increases with speed and I think you'll have a good answer.



That and you run out of gearing. Cars are made to run more from the line to 60ish. Mind you a corvette with a 6speed manual goes to sleep in 6th, but I am speaking in MOST type cars.


Corvette? C'mon, how bout a real car!
 

Zenmervolt

Elite member
Oct 22, 2000
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Originally posted by: Marlin1975
Originally posted by: conjur
Look for a graph showing how drag increases with speed and I think you'll have a good answer.
That and you run out of gearing. Cars are made to run more from the line to 60ish. Mind you a corvette with a 6speed manual goes to sleep in 6th, but I am speaking in MOST type cars.
Any American car with a good torquey V8 should have plenty of gear left. My Lincoln hits 55 in first and is only turning about 2,000 RPM at 75 in OD.

ZV
 

TheLonelyPhoenix

Diamond Member
Feb 15, 2004
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If there's a fuel efficiency difference anywhere between 65 and 75 mph in my Mazda 3, I haven't discovered it. Anywhere in that range yield about the same mileage with cruise control and the windows up (34-36 mpg).
 

holden j caufield

Diamond Member
Dec 30, 1999
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Originally posted by: aplefka
does driving over 60mph really this inefficient

Is that a statement? Is it in English?


either you're a grammer nazi or you're stupid if you don't understand the question (yes the grammer sucks but it's not hard to understand). No soup for yoooooo
 
Jan 31, 2002
40,819
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1-800-Bullshit

I made a seven-hour highway run in my old '93 Civic LX, averaging about 75-80mph the whole way. 42 mpg.

- M4H
 

aplefka

Lifer
Feb 29, 2004
12,014
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Originally posted by: holden j caufield
Originally posted by: aplefka
does driving over 60mph really this inefficient

Is that a statement? Is it in English?


either you're a grammer nazi or you're stupid if you don't understand the question (yes the grammer sucks but it's not hard to understand). No soup for yoooooo

You're telling me I'm stupid? Yup, I'm stupid because I can properly form sentences and questions. :disgust:
 
Jan 31, 2002
40,819
2
0
Originally posted by: aplefka
Originally posted by: holden j caufield
Originally posted by: aplefka
does driving over 60mph really this inefficient

Is that a statement? Is it in English?


either you're a grammer nazi or you're stupid if you don't understand the question (yes the grammer sucks but it's not hard to understand). No soup for yoooooo

You're telling me I'm stupid? Yup, I'm stupid because I can properly form sentences and questions. :disgust:

yes stupid you very is

up the shut f*ck

no0b

;) :D

- M4H
 

Kilrsat

Golden Member
Jul 16, 2001
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Originally posted by: MercenaryForHire
1-800-Bullshit

I made a seven-hour highway run in my old '93 Civic LX, averaging about 75-80mph the whole way. 42 mpg.

- M4H


I can get 20-22mpg while doing 80 in my El Camino... of course it was never the most fuel efficient vehicle in the first place. Will get roughly the same mileage even at 65.

 

Yellow Dog

Banned
Apr 1, 2005
256
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0
You have to keep in mind that all of the mileage ratings on new cars, that the highway MPG listed is tested at 52 MPH or something close to that, nothing that has anything to do with actual "highway speeds". Just another duping of the public by the auto industry with the governments blessings.
 

ElFenix

Elite Member
Super Moderator
Mar 20, 2000
102,402
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Originally posted by: Yellow Dog
You have to keep in mind that all of the mileage ratings on new cars, that the highway MPG listed is tested at 52 MPH or something close to that, nothing that has anything to do with actual "highway speeds". Just another duping of the public by the auto industry with the governments blessings.

i get my rated mileage.
 

glorifiedg790

Banned
Mar 29, 2005
301
0
0
Originally posted by: Zenmervolt
Originally posted by: Marlin1975
Originally posted by: conjur
Look for a graph showing how drag increases with speed and I think you'll have a good answer.
That and you run out of gearing. Cars are made to run more from the line to 60ish. Mind you a corvette with a 6speed manual goes to sleep in 6th, but I am speaking in MOST type cars.
Any American car with a good torquey V8 should have plenty of gear left. My Lincoln hits 55 in first and is only turning about 2,000 RPM at 75 in OD.

ZV

How about a 98 taurus?
 

conjur

No Lifer
Jun 7, 2001
58,686
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0
Originally posted by: glorifiedg790
Originally posted by: Zenmervolt
Originally posted by: Marlin1975
Originally posted by: conjur
Look for a graph showing how drag increases with speed and I think you'll have a good answer.
That and you run out of gearing. Cars are made to run more from the line to 60ish. Mind you a corvette with a 6speed manual goes to sleep in 6th, but I am speaking in MOST type cars.
Any American car with a good torquey V8 should have plenty of gear left. My Lincoln hits 55 in first and is only turning about 2,000 RPM at 75 in OD.

ZV

How about a 98 taurus?
Sucks no matter *what* the speed or gear is! :p

 

Kilrsat

Golden Member
Jul 16, 2001
1,072
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0
Originally posted by: Yellow Dog
You have to keep in mind that all of the mileage ratings on new cars, that the highway MPG listed is tested at 52 MPH or something close to that, nothing that has anything to do with actual "highway speeds". Just another duping of the public by the auto industry with the governments blessings.


In 1987 my car was rated at 18/22 for city/highway. I still get 21-22 on the highways, even at speeds of 65+mph. Where's this grand conspiracy?
 

Actaeon

Diamond Member
Dec 28, 2000
8,657
20
76
Aside from coasting and those other "tricks", you will always get the best gas mileage in your highest gear, at the lowest cruising rpm (typically 1500~), thats typically around 35-40mph in most cars.
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
44
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Originally posted by: glorifiedg790
Originally posted by: Zenmervolt
Originally posted by: Marlin1975
Originally posted by: conjur
Look for a graph showing how drag increases with speed and I think you'll have a good answer.
That and you run out of gearing. Cars are made to run more from the line to 60ish. Mind you a corvette with a 6speed manual goes to sleep in 6th, but I am speaking in MOST type cars.
Any American car with a good torquey V8 should have plenty of gear left. My Lincoln hits 55 in first and is only turning about 2,000 RPM at 75 in OD.

ZV
How about a 98 taurus?
V8? And I doubt the SHO V8 is a good example since it's performance tuned.

Though to be honest, most American cars with more than a 4 cylinder have a pretty tall overdrive gear because of all the highway travel.

ZV