EPA estimates skewed

[nemo]

Originally Posted by Kodak

I don't even bother trying to estimate a percentage. I just know that my commute is not a true highway trip, but has fewer stops than a real city trip. So it's somewhere in the middle, just not sure where.

If you have a GPS and look at the stopped time verse travel time it will give you an idea of your type of commute. It could be expressed as a percentage, if someone wanted to go to that much trouble.

[d0sitmatr]

Originally Posted by graydonengineering

With the roads around here I get much better mpg in the city so the proposed ratio would put me much further ahead of EPA than I am. The speeds are 45 in town and the lights are far appart. I anticipate, coast, key off and fight my way up to a 30-35mpg average. On the highway it's nothing but open thottle, no cheating and my mileage is closer to EPA. My FE falls off a cliff once I exceed 50 mph. I hope to change that with a full belly pan.

that is where Im at as well.
I am pushing 30mpg, but that is almost all strictly city driving. once I hit the hwy, my FE actually goes down... and nothing Ive been able to do so far has really made much of a difference.

[Kodak]

Originally Posted by nemo

If you have a GPS and look at the stopped time verse travel time it will give you an idea of your type of commute. It could be expressed as a percentage, if someone wanted to go to that much trouble.

That's a cool idea. Never thought of that.

The EPA city test has idling down as 18% of the time, and Highway is of course 0 percent. So I guess if the combined rating has 55% city and 45% highway...approx. 10% idle time would be a combined trip. Good info.

[gone-kl]

Originally Posted by capnbass91

Accelerating slowly goes against my racing video game upbringing, but it's becoming more natural, and my mpg is showing it.

If I drove in real life the way I drive in racing video games, I'd have died a long time ago, taking the car and maybe a few innocents with me.

[Mustang Dave]

In line with what a few members have posted, I generally get better fuel economy commuting than I get on road trips. YMMV.

[capnbass91]

Originally Posted by micman

If I drove in real life the way I drive in racing video games, I'd have died a long time ago, taking the car and maybe a few innocents with me.

Hahahaha! Not GTA status! I mean that in racing games the goal is to be first by being the fastest. I just think that playing those games as a child it translates to some adults in a real car, gotta be the fastest and be ahead of the others.

But I'm working on slowing it down, accelerating with mpg in mind.

[tjts1]

Originally Posted by capnbass91

Combined EPA estimated mpg is based on 45% highway and 55% city driving, FEcomb = 1 / (( .55 / city FE) + (.45 / hwy FE))

That isn't fair for those of us that do far more city than highway driving, where it should be closer to 10 and 90%, makes us look bad! That ratio would be:
FEcomb = 1 / (( .90 / city FE) + (.10 / hwy FE))

Using that average and excluding my recent trip to Twin Lakes, my combined mpg rating for my car would be 18.5, which is exactly where I'm at

Anyone else do far more city than highway driving? And find that the 45-55 ratio doesn't correctly apply to you?

Does it really matter?

[gone-ot]

...it's an ESTIMATE!

...made by the GOVERNMENT!

...what do you EXPECT?

[sid]

I do far more city driving than highway. But I typically get better FE around town (about 28 mpg) than what the EPA rates my vehicle on the highway (27 mpg). So, even though I typically get around 35 mpg highway driving with no kayaks and racks, since most of my driving is local, my average is between 29 and 30 mpg.