Just finished our third tour of the United States. This time in our 2006 Honda S2000 (Laguna Blue Perl )



Overall I'd say it's not bad results, especially for a car quoted at 20/26MPG. I shifted the PPM column to match up with the fuel that was being used, but I suppose I should have done that for MPG and Miles as well. *shrug*, you get the idea.

For those attempting to track our route, here is a link to a Google Map that roughly illustrates the path we took.

Images from the trip. I haven't done my usual captioning and map placement yet, but that'll happen tomorrow while I'm trying to stay awake at work.

And to anyone asking why we didn't take our '04 HCH, obviously you've never driven a convertible through the mountains (: Additionally, this being our third long road trip, we wanted to keep the tradition of taking a different car each time. Hmm, that means we need a new car by this time next year ...

 

Good data keeping but the only thing missing are the elapsed time per segment. When doing trips at highway speeds, it helps if you can use cruise control and the time to confirm the speed. Then vary the speed in say 5 mph segments to plot the MPG vs MPH. This helps identify optimum cruise speeds for best mileage. Just a suggestion.

Bob Wilson

 

Too true. However, in this situation, the terrain was massively different per tank. For example, <27MPG was climbing the Rocky Mountains, >29MPG was coasting down them (:

We used cruise control A LOT. My rule of thumb is 110% of the speed limit, rounded down. For 65MPH limit I do cruise at 71MPH. For 75MPH limit I do 82MPH.

Interstate Speeds (according to my feeble memory)
Arkansas 70
Oklahoma 75
Kansas 75
Colorado 75
Utah 75
Idaho 75
Oregon 65
Washington 75
Canada 100km/h (62mph)
Montana 75
North Dakota 75
Minnesota 70
Wisconsin 65
Illinois 70
Missouri 70

 

Owch, I can't cut-and-paste these into the spreadsheet image. BTW, don't worry too much about variability. My recent trip to NC suggests that the mileage effects of modest hills on mileage is not that significant at these speeds:

The hills are effective energy storage systems that store energy on the climb and return it on the descent. At highway speeds, the air drag at 60-75 mph easily absorbs the returned energy. The only problem is higher power settings going up the hill can put the engine in less fuel efficient rpm and power ranges.

Ken@Japan has in the past pointed out that the starting and ending altitudes are also important. You've provided enough information about the cities that we can add the altitude changes. I'll try to post that later this evening (got to scamper off to work.)

Bob Wilson

ps. Would you consider posting the comma delimited values from your spreadsheet? It would make subsequent analysis a lot easier.

pps. I am quite happy to share my gps+scanner data but it is a little large. The spreadsheet is already at 27 MB. But if you have an interest, send me a PM and we can work out the logistics.

 

One big question;
In those 6000+ miles, did you have your vehicle serviced?
Or did you use those long life synthetic oils?

 

Wow, I didn't know so many placed had 75 mph speed limits. I don't think I've even ever seen a 75 mph sign. I thought 70 was standard and some places were slower.

 

Long life synthetic ... and I sort of overshot it too.

75 has become quite common actually. It's kind of nice.

 

 

Thanks,

I looked for correlations with speed and distance but nothing stands out. Maybe next year and possibly with the local wind direction(head, side, rear) and elapsed time for each segment.

Bob Wilson

 

That would be me ... I usually refer to myself in pictures as "some dude". Not really to stay anonymous, but rather for the sake of humor.