Volumized trending on gas mileage

Are you still doing this? I'm about to drive an 07 accesscab V6 across the country and back, and to some degree I'm willing to to modify the conditions to achieve some higher accuracy. There's a fair amount of potential already:

- The outbound route (slightly scenic) looks to be about 3,000 miles -- if I'm lucky, 170 gallons), or a fairly large sample size on a single vehicle

- Load will vary by maybe a hundred pounds from beginning to end (food/water; trading passengers within caravan)

- The other vehicle is a heavily-loaded Subaru stationwagon, so I think total speed will be both low and consistent

- Thanks to my GPS unit, I can record avg. speed/peak speed per tank with complete ease

- The truck is 100% stock, just hit 14k miles (post-break-in mileage change?) -- although, I am trying to get a used cap sometime this week.

- It gives me a nice excuse to do all the driving.


It wouldn't be that hard, or (in comparison to the overall cost) much more expensive, to stick to a single brand and octane of gas. What variables does that leave, in terms of getting a pretty good sense of real-world highway mileage? Or maybe the question is: what information do current statistics really lack, that we could design a good test against?

 

It's been quite a while since I got any new data to add but yeh, I'm still incorporating it as it comes. What would be great is if there was a way to download the data from a scangauge or similar and get mph, rpm, hp data over time. The idea would be to produce a report detailing the optimal mph, rpm etc for highest mpg.

I've got a trip from VA to Michigan coming up soon so I'll vary my mph using the cruise control and see what the mpg is. Not perfect but would be somewhat indicative.

Keep sending the data folks.

Thanks

 

cvillechopper Are you taking into consideration that some of the stock trucks have smaller tires than the truck thinks they have. The 245 series tires are incorrect for the truck making the readings all wrong. Mine is 2.7mph slower than the speedo reading and the mileage is off so would be the rpm. Sorry if someone already brought this up.

 

I think that's normal. My Corolla was off about 3mph with stock tires, same as my Tacoma.

 

Yes and No. I am recording the tire size (it's included on the spreadsheet of information needed) but I'm not adjusting for a certain tire size. You have to take some things for granted or the analysis gets very complicated. If we get enough data I can run the samples by different tire sizes for the same configurations and see what the impact is, maybe even do some factoring to eliminate the speedo calibration difference.

 

After all your hard work and time I just didn't want anything to come back and bite you in the rear. You get rep for the job your doing. Thanks!

 

James, It appears that you have started something to take up some of your spare time By the looks of your charts so far you have got it under control! !! Keep up the good work and THANKS for all you are doing! !!

 

That's pretty possible -- it might even exist already. There are a number of windows programs to interpret ODBII, and some probably have a logging feature of some sort. If you could get a log in some consistent format, a simple script could easily convert to a text file that Excel will take, giving us easy graphing..

I suppose the issue is doing it cheap enough and simply enough that we could convince people with laptops to do it & provide data. In which case I would say that enough people have a ScanGauge, and the Scangauge cord looks to end in an RJ-45 (ethernet) plug, that if someone is savvy enough to make a simple ODBII logger, your wish could be fulfilled.

 

I'm still keeping track of my tanks. Just haven't sent them in since beginning of April. I've got 4 new tanks and probably another 1-2 after this weekend.