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What highway speed results in your best fuel economy?

Posted: Fri Jan 15, 2010 4:32 pm
by gorgecat
Still on my first couple tanks of gas with a used 2007 Vibe. Interested to see what folks get the best MPG with.Thanks.

Re: What highway speed results in your best fuel economy? (gorgecat)

Posted: Fri Jan 15, 2010 10:28 pm
by zionzr2
generally keeping it under 70 mph and 3K rpm will yield the best mpg results.

Re: What highway speed results in your best fuel economy? (gorgecat)

Posted: Fri Jan 15, 2010 11:31 pm
by Caretaker
at least 90 mph. That way I get to my destination before the gas needle has a chance to go down.

Posted: Sat Jan 16, 2010 11:36 am
by midnighthunder89
55 mph is usually the most fuel efficient. I just never do my highway driving contains driving for 8.5 hours stopping once for gas. if I were to go 55 it would take 14 hours. not worth it for me.

Re: (midnighthunder89)

Posted: Sat Jan 16, 2010 2:07 pm
by SmAshley
I don't have the new engine but my 1zz 2003 I get 130 km/h I got to Calgary from Edmonton = 300k on 1/2 tank but I find if we use the cruise it makes it way worse

Re: (SmAshley)

Posted: Sun Jan 17, 2010 12:29 am
by lovemyraffe
Quote, originally posted by Caretaker »at least 90 mph. That way I get to my destination before the gas needle has a chance to go down. Sounds pretty accurate to me.The speed limit around here is 75, and doing 75-80 mph I usually get 33-35 mpg.

Re: (lovemyraffe)

Posted: Sun Jan 17, 2010 1:36 am
by ponta2147
Quote, originally posted by lovemyraffe »Sounds pretty accurate to me.The speed limit around here is 75, and doing 75-80 mph I usually get 33-35 mpg.SO Jealous. Around Chicago it rarely gets above 55mph for the speed limit, so I'm stuck around 65. I can't wait for our road trip next week so I can make my car go an actual speed.

Posted: Sun Jan 17, 2010 7:37 am
by Old Tele man
...technically, you'll get the best fuel economy in the highest gear, at the lowest rpm that doesn't "lug" the engine....which is typically somewhere between 45 and 55 mph, depending upon the transmission and axle gearings in the car....rememeber aerodynamic "drag" increases as a "squared" function of speed, so the faster you go, the MORE hp you need to do so.note: "lug" = loading engine so much that it wants to stall.

Re: (Old Tele man)

Posted: Sun Jan 17, 2010 9:07 am
by jake75
The longest trip I have is usually 615 miles. That usually involves 10.25 hours of driving - an average of 60.0 mph. To get that average I have to be hitting 70-75 at times. If I dropped that by 10 mph it would take me about 1 more hour. Scenario 1 at 31 mpg = 19.84 gal of gasScenario 2 at 34 mpg is 18.09 gal of gas.The cost of 1.75 gal of gas is less than $5.00. So if that saves me 1 hour I am paying less than minimum wage for the privilege.

Re: (jake75)

Posted: Sun Jan 17, 2010 10:05 am
by ponta2147
Quote, originally posted by jake75 »The longest trip I have is usually 615 miles. That usually involves 10.25 hours of driving - an average of 60.0 mph. To get that average I have to be hitting 70-75 at times. If I dropped that by 10 mph it would take me about 1 more hour. Scenario 1 at 31 mpg = 19.84 gal of gasScenario 2 at 34 mpg is 18.09 gal of gas.The cost of 1.75 gal of gas is less than $5.00. So if that saves me 1 hour I am paying less than minimum wage for the privilege.I like your thinking!

Re: (Old Tele man)

Posted: Sun Jan 17, 2010 1:17 pm
by Maoule
[QUOTE=Old Tele man]...technically, you'll get the best fuel economy in the highest gear, at the lowest rpm that doesn't "lug" the engine.With the dbw system, can you "lug" the engine? If so, is it the same as the cable/linkage carbs?

Re: (Maoule)

Posted: Sun Jan 17, 2010 3:03 pm
by star_deceiver
90-100km/h in the summer, steady throttle with NO aggresive driving.... not in most people daily drive....I get about 8L/100kms on my trips to Vancouver from Vernon, BC taking 97C and 5 (google maps) in winter with heavy studded winter tires doing about 130km/h, 9L/100kms when I push 140km/h+ and having the weather co-operate... Summer mileage at those speeds is a little betterQuote, originally posted by SmAshley »I don't have the new engine but my 1zz 2003 I get 130 km/h I got to Calgary from Edmonton = 300k on 1/2 tank but I find if we use the cruise it makes it way worse That's a boring drive.... not quite as boring as the drive from Sacramento to LA but still, when I go to Red Deer I usually fly around 140km/h and still get passed by loads of people...

Posted: Tue Jan 19, 2010 11:36 pm
by DrunkenMonster
I got 35 mpg doing 80-85 in the middle of the night with no traffic coming back from Alabama.

Re: (SmAshley)

Posted: Wed Jan 20, 2010 4:25 am
by bull77
Quote, originally posted by SmAshley »I don't have the new engine but my 1zz 2003 I get 130 km/h I got to Calgary from Edmonton = 300k on 1/2 tank but I find if we use the cruise it makes it way worsenice!! i get about 300 doing 120

Re: What highway speed results in your best fuel economy? (gorgecat)

Posted: Fri Jan 22, 2010 5:56 am
by omgLIFT
when I had my 1zz Corolla the best speed to maintain on the highway to achieve the best gas mileage was definitely 55mph ... it can get frustrating watching everyone cut you off or fly by you though so even driving around 65 is still being conservative and will yield great gas mileage.If you want try looking into some "hypermiling" forums for more info and great driving techniques to help you get the most amount of miles during a trip.

Re: What highway speed results in your best fuel economy? (omgLIFT)

Posted: Sat Jan 30, 2010 9:30 am
by mikellini
Theoretically, you get the most power per unit of gasoline at peak volumetric efficiency, which is pretty well the same as peak torque. So, your ability to overcome drag is highest at peak torque, which means that depending on your engine speed and vehicle speed at a given level of drag, you might have better fuel economy at higher RPMs than lower. However... in reality, gear ratios aren't ever really tuned for this from the factory, and so you probably get the best fuel economy in any given car while in the highest gear, and the lowest RPM you can drive at (as mentioned before).

Posted: Sat Jan 30, 2010 12:41 pm
by rated_w
I find that doing about 85 kph is the most fuel efficient, being on a 2004 pont vibe fwd auto

Posted: Sun Jan 31, 2010 8:57 am
by Old Tele man
...granted, this is a Corvette Z06 and not a Vibe, but this picture clearly illustrates the inversely-declining relationship between mpg and mph--going faster, lowers your fuel economy!Note:5 / 1000 = 5th gear, 1000 rpm6 / 820 = 6th gear, 820 rpm6 / 1500 = 6th gear, 1500 rpm, etc.

Re: (Old Tele man)

Posted: Sun Jan 31, 2010 9:19 am
by keithvibe
somehow if i'm driving a vette, gas mileage is the last thing on my mind.