Did almost as well in the city as on the highway
 

About 80% of my driving is country highway (80km/h, 50mph), and about 20% light city (city of about 200,000).

Yesterday, for the first time since I'd started concentrating on eco-driving (I won't quite call myself a hypermiler yet) two weeks ago, was the first time I needed to do some city driving.

I have the Torque app set up in my car, and I was pleased to find that my city fuel consumption was only marginally higher than my highway fuel consumption on the three previous days. Torque had recorded an average of 6.1L/100km (38.5mpg) for three days of highway, and 6.2L/100km (37.9mpg) for a 15 minute city drive, starting from a cold start (on a warm day).

Note that my actual fuel economy the last few tanks has been somewhat better than this, around 5.6L/100km (42mpg). The Torque app just isn't fully calibrated yet, but the relative comparison between city and highway on the same tank is probably still valid.

It kind of makes sense, since there's a lot more opportunity for improvement in stop-and-go city driving than in a steady cruise on mostly level ground.

By the way, a quick and easy way to convert from L/100km to mpg or vice versa is to divide into 235:

235 / X mpg = Y L/100km
235 / Y L/100km = X mpg

Very nice! You're well on your way to being a hypermiler. :) Most of us can eek out better mileage in the city than on the highway. The aero losses are pretty big once you get up to speed. In the city, if you can minimize brake use, you're golden.

I guess I'd better get to work on those aero mods to improve the highway fuel economy.

With a small pickup I almost always get better mileage in light to moderate down traffic than open highway. The poor drag coefficient of a truck really makes a difference.

I did this seven or eight years back: to more closely approximate Hwy mpg while in the city. The average speed is better (average, not absolute), the difficulty is in avoiding stops.

One has to be rigorous about the fewest engine starts. Constant use of engine block heater. And route planning.

The key was that, 90% of us go to 90% of the same places 90% of the time. Besides work, the usual round of errands.

I had a couple of routes to accomplish it all. Both involved using a freeway to go to the farthest point first. Then, no left turns, park for easy egress, etc. Used a four-piece grille block to force coolant temps.

And, as discipline, no driving at all at least one weekend day.

20% improvement from previous. I use 24-mpg for highway (in a pickup loaded 1100-lbs over baseline). City, in this period was 22 versus 18.

I've detailed this at greater length elsewhere. And on RV plus truck forums that to do as much would have paid for 5000-miles of vacation towing of my travel trailer based on a solid average; and at the then current fuel price

No one has ever taken me up by interest. This was always posted to specific threads on fuel economy. Including this forum around RV topics.

There was no sacrifice in convenience. I never did walk, bicycle or do other substitutions. No public transport. Nor shift a trip to my wife and her car.

As always, it's the percentage gain over the baseline.

Took it as a challenge from Diesel Dave as he set his record-breaking distance from one tank of fuel
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