MPG local vs freeway

[delsol7]

I have 2002 CVT.
I owned it for 2 weeks and I'm getting bit strange MPG on freeway and local.
Isn't it usually freeway get higher mileage than local?
When I run on local, I tend to stay between 40 ~ 45 mph since it gives optimum MPG. It sometimes gives 70 MPG on local. Now on freeway, I stay between 65 to 70 mph. Thing is.. it's hard to keep up with higher than 50 MPG. Slight push on gas drops MPG down below 50 MPG and if I try to stay higher than 50 MPG then speed starts to drop.

Is there something wrong with car or am I missing some technique?

[red1dr]

Hopefully the CVT whizzes will chime in here, but this sounds perfectly normal for an MT Insight-I. For the MT Insight-I, the optimal mpg zone in 5th gear seems to be around 35-45mph. Most cars get better mpg's at slower speeds, except for some special cases such as transmission lockup issues for an AT.

At higher speeds, the engine is working harder to overcome air resistance and tire flex, and that apparently takes the relatively small Insight-I engine out of its most mpg-efficient zone.

[BrianZ54]

Yeah, Delsol, that sounds about right. I've found optimum speed to be somewhere between 40 and 50 mph. You could easily average well above 65 mpg if you could drive those speeds all day. About 90% of my normal weekly driving is highway and I usually drive between 68-73 mph just to keep from getting run over. When I bought my car I reset the lifetime mileage which now stands at 53.3 mpg, that means I do a little better in summer to balance out the lower winter numbers.

I look at it this way - I replaced a compact car that was averaging about 27 mpg on the local roads. I'm spending about $110 less a month on gas alone. On a straight comparison it looks pretty positive.

As you become more familiar with some of the easily applicable hypermiling techniques you should see your mileage rise a bit. I can't recall if you had firmed your tires up but that helps quite a bit. I run 44 lbs locally and pump them up to about 48 when I travel. I know a lot of people here run them higher but my local secondary roads are pretty poor -you hit a typical dirt road pretty hard at 50 psi or higher. It's more realistic to compare with your last ride, everybody's road conditions and speed laws vary.

Brian

[timny1984]

I have a 2001 CVT and have averaged 70mpg so far with it over 6k miles with zero mods(unless you count the air horn i added). My car has 177k miles on so it has seen its fair share of road ways. I drive 47.6 miles round trip to work and that's 95% highway where the speed limit is 55mph. I really had to learn the right speeds to hit at each point on the way to work. I actually get above 71mpg(bad day) and the max i got was 82.2mpg round trip. I try to stay around the 75 or above depending on how much traffic there is.
Now ignore the extreme number. A normal day for me is staying around 51-57mph. There are certain points where that speed will drop to 48-50mph but i rarely try to drop below 50mph, and there are times where i will hit 60-62mph. My thought is if people think it's ok to go 7-10mph over the speed limit why can't i go 5-7 under the speed limit? I only do this when there is a lane to pass as to not obstruct the flow of traffic or make a dangerous situation. The point of this is if you learn your roads and you will reap the rewards in mpg's.

Now here are some redundant tips to get these numbers,
-you can't be holding a constant speed the whole time, try holding a constant throttle position and don't worry about the people behind you. they will pass if they get annoyed.
-fill those tires up, I'm running between 55-60psi. I don't notice poor traction or a super ruff ride, but run what you are comfortable with. I did notice poor traction in the rain when i needed new tires, and after new tires the rain handling it 100% better.
-When accelerating at highway speeds don't try to jump up 3-5mph in a few seconds. Give a tiny bit more gas and let the speed increase gradually, in no time you'll be 5mph higher and really that gradual increase doesn't seem to take to long after getting used to it.

Running at speeds between 60-70 isn't going to get you super high numbers, but driving correctly at those speeds will get you decent numbers. i tend to stay away from 70mph. but when i do i try to find a vehicle to follow just to get some sort of drafting off of. Between 60-70mph you should be able to get the mid to low 60's mpg.

One last thing, i really think that driving with a shoe or flipflop on it is almost impossible to get the max mpg out of these cars. I take my shoe off when i drive, you really can feel the throttle alot more that way. Now when the western NY winters come around i'm not sure what i'm gonna do. but for now and the 80 degree temps i'll be fine taking a shoe off.

there's my 2 cents


Tim

[delsol7]

Thanks to the replies.

Seems like I need to start on pressure change before anything. I will try 50 psi.
I came from Lexus ES300 so it is definitely much better MPG compare to Insight. I think my maximum MPG was about 28 to 30 MPG max on that car. Almost double the MPG. However, it's still interesting to think that highway MPG is lower than city MPG.

One thing I noticed that I become very conservative driver even if I was driving the ES300 today. Without even trying, I was running 60 mph on freeway.