Set my cruise control to 65

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I enjoy driving in the snow, and at 30k/yr I have done my fair share. But rarely have I seen any of the high speed drivers in the ditch--the ones who flew by me, that is. Random people in the ditch, yes. But I can only recall one incident of someone passing me, then me passing them as they crashed--and that was a Jeep who spun out in a rainstorm.
 
It makes you wonder if everyone drove this speed on average on the interstates what fuel consumption would be on a national scale.
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Most vehicles have optimal efficiency around 55-60 MPH. Is it really that necessary to drive 70+ at all costs just to try to beat a couple red lights, sections of traffic, and only save yourself maybe 10 minutes? It's like everyone can't wait to get somewhere so they can smart phone it up again and nowadays the slow drivers must be the ones texting. LOL.
 
Why 55? Why not 50? Or 40? Or zero?

This thread has brought a lot out of the woodwork, I'll say that. Did Canada even implement a NMSL? Not that I'm aware of.

And you are aware that the U.S. NMSL saved less than 1% right?
 
Originally Posted By: kschachn
Why 55? Why not 50? Or 40? Or zero?

This thread has brought a lot out of the woodwork, I'll say that. Did Canada even implement a NMSL? Not that I'm aware of.

And you are aware that the U.S. NMSL saved less than 1% right?

Try it, 55mph vs 75mph is probably near 20% less fuel burned. Seems crazy that it wouldn't make more than 1% difference overall even if many people don't get on a freeway everyday.
I think 55 was chosen as its about as fast as you can go without starting to waste a lot of fuel pushing air around.
 
Originally Posted By: kschachn
Why 55? Why not 50? Or 40? Or zero?

This thread has brought a lot out of the woodwork, I'll say that. Did Canada even implement a NMSL? Not that I'm aware of.

And you are aware that the U.S. NMSL saved less than 1% right?


Exactly. All the 55mph NMSL established was that the people who came up with the idea were even bigger imbeciles than their counterparts in East Germany, which had a NMSL of a blistering 62mph...
 
I tried going 65 mph on the highway with my commute but then I started going 75 mph and my mpg hasn't changed at all, might be even better. Probably a TDI thing though.
 
^^^ I think that's an aerodynamics and TDI thing.

My tundra averages 16-17 on my in-town commute which is mostly 35 and 45 mph. Best ever for an in-town tank is 18.

As soon as I break that habit and do some highway time, it drops. So-- my highway mileage is worse than my in-town commute mileage, which includes some stops and normal errands. On trips of 65-68, it sits at 16mpg.

It's been over 70 fewer than like 5 times. You can feel the wind resistance stack up starting around 60. We take the other car for highway trips unless we are going camping.
 
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I am going to enjoy driving to Fontana next Thursday for the Indy race. I will be on the 210 for a long time and will completely enjoy setting the cruise to 85-90 and have my doors blown off by other cars. I'm not joking, I actually do enjoy the 210.
 
Originally Posted By: ltslimjim
It makes you wonder if everyone drove this speed on average on the interstates what fuel consumption would be on a national scale.
21.gif


Most vehicles have optimal efficiency around 55-60 MPH. Is it really that necessary to drive 70+ at all costs just to try to beat a couple red lights, sections of traffic, and only save yourself maybe 10 minutes? It's like everyone can't wait to get somewhere so they can smart phone it up again and nowadays the slow drivers must be the ones texting. LOL.

Some cars have highest MPG at 35-40 MPH, others at 45-50 MPH.

The highest MPG is top gear without engine lunging.

If a car gets highest MPG at 50 MPH, should that car be driven at that speed on Interstate Highways ?
 
I generally set the cruise control to 20 MPH over the speed limit in the greater New York City area, which for me generally means cruising at 75MPH in 55MPH zones beyond city borders on limited access highways. I don't zip in and out of lanes, only merging merging when there is a sizeable gap.

I've done this for many years, passing police radar traps on quite a number of occasions. Every now and then at that speed I notice someone quickly coming up on my rear, pull over and it is a police cruiser passing me. I've yet to be stopped by the police.
 
Originally Posted By: IndyIan
Try it, 55mph vs 75mph is probably near 20% less fuel burned. Seems crazy that it wouldn't make more than 1% difference overall even if many people don't get on a freeway everyday.
I think 55 was chosen as its about as fast as you can go without starting to waste a lot of fuel pushing air around.


According to the government and others it was less than 1%.
 
Originally Posted By: HTSS_TR
Originally Posted By: ltslimjim
It makes you wonder if everyone drove this speed on average on the interstates what fuel consumption would be on a national scale.
21.gif


Most vehicles have optimal efficiency around 55-60 MPH. Is it really that necessary to drive 70+ at all costs just to try to beat a couple red lights, sections of traffic, and only save yourself maybe 10 minutes? It's like everyone can't wait to get somewhere so they can smart phone it up again and nowadays the slow drivers must be the ones texting. LOL.

Some cars have highest MPG at 35-40 MPH, others at 45-50 MPH.

The highest MPG is top gear without engine lunging.

If a car gets highest MPG at 50 MPH, should that car be driven at that speed on Interstate Highways ?


How many cars today aren't in high gear at 55?
 
Originally Posted By: Jarlaxle
Originally Posted By: HTSS_TR
Originally Posted By: ltslimjim
It makes you wonder if everyone drove this speed on average on the interstates what fuel consumption would be on a national scale.
21.gif


Most vehicles have optimal efficiency around 55-60 MPH. Is it really that necessary to drive 70+ at all costs just to try to beat a couple red lights, sections of traffic, and only save yourself maybe 10 minutes? It's like everyone can't wait to get somewhere so they can smart phone it up again and nowadays the slow drivers must be the ones texting. LOL.

Some cars have highest MPG at 35-40 MPH, others at 45-50 MPH.

The highest MPG is top gear without engine lunging.

If a car gets highest MPG at 50 MPH, should that car be driven at that speed on Interstate Highways ?


How many cars today aren't in high gear at 55?
My car gets into 6th gear (6 speed auto) at about 40-45 mph.
 
Highway speeds, isn't that the speed women drive thru Walmart lots????????????????? Walmart lots have to be more dangerous then interstates, imho
 
Originally Posted By: Jarlaxle
Originally Posted By: HTSS_TR
Some cars have highest MPG at 35-40 MPH, others at 45-50 MPH.

The highest MPG is top gear without engine lunging.

If a car gets highest MPG at 50 MPH, should that car be driven at that speed on Interstate Highways ?


How many cars today aren't in high gear at 55?

Most if not all cars with 6-7 speed(or less) AT would be in highest gear around 40-45 MPH or even slower on level ground.

My S2000 with 6-sp manual get cruise at 38 MPH on 6th on flat surface, the gas mileage at this speed is more than 45 MPG. At 55 MPH gas mileage went down to 32-34 MPG.

As I said, the highest gas mileage on level ground is the slowest speed at highest gear without engine lunging, which can be as slow as 40-45 MPH or slower.

Why don't we have national speed limit at 45 MPH to get the best gas mileage for more than 95% of all vehicles on the road ?
 
@HTSS_TR

My implication is for most automatics I suppose. For example, I have to drive my Fit 55 MPh or so to get relatively close to the MPG of my BILs overall economy; who has the 5-speed manual and can get much better MPG even doing 75-80; by a sizable margin.

Granted, he does have a header, 'warm' air intake, and better tires / slightly lowered ride. However, the primary difference being he has more returns for driving faster where as if I drive 75 I get about 70-80 less miles per tank comparatively. Even though my rpms are lower from the taller gearing on my 5-speed a/t, I have less pushing power as a result and the torque converter unlocks. So, the wind resistance on the vehicle reduces my fuel economy the faster I drive in this relative speed range. He does have an older ScanGauge-II that he uses to cheat, though.
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The point isn't to drive at your optimal MPG, just that most probably would benefit from slowing down some. Not necessarily to 55 or a specific number, but considering 80+ is the standard these days even driving 70 instead would probably save some fuel overall.

This is why I stay in the 2nd lane from the right on the interstate and go around 60-65.
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If you want to go around I'm not in your way and will even speed up for mergers, etc. and being the slower vehicle I obviously am more inclined to yield and observe traffic behind like clockwork.

I suppose my post was too vague to begin with. I find it highly frustrating that my 23 year old Honda Civic VX with 290k miles gets stolen and I "upgrade" to a 2007 used Fit and get worse MPG even at it's "best" 55 MPH spot to eek out barely 30 MPG where as the other car got 35 MPG not even trying (70+ MPH interstate constantly, up to 2200 RPMs in 5th and you can stay in lean burn to around that point and not trigger vtec).

Oh, and I would've gotten another stick but considering the unplanned purchase (my only vehicle) and that most Fits are equipped with A/Ts for this vintage 07/08 (our price range) we settled. My wife's health requires us have an automatic now if she wants to drive herself someplace and since she can't use her legs for shifting anymore we used the "unfortunate" opportunity to convert. Sort of a blessing in disguise, but I would've liked some money out of that other car back considering the loss in fuel eco. Call me salty.
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Originally Posted By: ltslimjim


This is why I stay in the 2nd lane from the right on the interstate and go around 60-65.
smile.gif
If you want to go around I'm not in your way and will even speed up for mergers, etc. and being the slower vehicle I obviously am more inclined to yield and observe traffic behind like clockwork.


If you are the slowest traffic (are you at 60-65?), why are you not in the first lane from the right?

That is what I would do... in fact, that is what I do, even if I drive faster than 65... until I have to overpass someone, car or truck.
 
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Originally Posted By: HTSS_TR
Why don't we have national speed limit at 45 MPH to get the best gas mileage for more than 95% of all vehicles on the road ?


YES! HTSS, please come demonstrate for all of us how well that would work, driving across Texas on I-10, from Orange to El Paso.!

Please do it, lead by example!
 
Originally Posted By: gfh77665
Originally Posted By: HTSS_TR
Why don't we have national speed limit at 45 MPH to get the best gas mileage for more than 95% of all vehicles on the road ?


YES! HTSS, please come demonstrate for all of us how well that would work, driving across Texas on I-10, from Orange to El Paso.!

Please do it, lead by example!

I don't intend to drive 40-45 MPH on highway with speed limit of 65 MPH or higher. On some stretch of I-15 and I-10 in CA-NV-AZ 85-90 MPH seems slow, reasonable speed should be 95-100 MPH.

My respond was to a poster about national speed limit of 55 MPH some years ago. He stated that 55 MPH was chosen because it yielded the best gas mileage.
 
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