SuperMID M1, MPG Computer

[krousdb]

I had mentioned earlier that I was looking for a mileage computer for my del Sol. What I didn't mention is that I had one for my Prius for an event that I partipated in last summer. It is called the SuperMid. This is a very long thread but you can see some pictures of the device when we reported mileage after each shift.

Why did I need a mileage computer for the Prius when it already has one???? Well, we were able to exceed the 99.9 MPG limit. The SuperMID shows km/l up to 99.9, which translates to 235 MPG.

http://www.greenhybrid.com/discuss/prius-ii-100-mpg-marathon-attempt-live-updates.3041.html?page=1&pp=10&highlight=marathon

I sent the SuperMID back home to my friend Yoshi in Japan, but I just got a message from him that the same device will work on my del Sol. I just need to calibrate it by changing the parameters for fuel injection duration and distance values. So it is back on it's way to Pittsburgh as soon as he makes some mods to it. I expect it by the end of the month. In the mean time I just need to locate the speed sensor and injector wires to tap into. And since I am in no danger of exceeding 99.9 MPG, I will calibrate to miles per gallon instead of km/l. The labels will still read km/l however.

Cool stuff. I will post install pics and data when I get the SuperMid

[Matt Timion]

Awesome. I wrote the company that makes the oztrip asking if I could buy either a kit or an assembled unit. Their response was that the oztrip computer is no longer in production and that they were working on a new model. This new model, however, will not be completed for a very long time, they say.

Hopefully the SuperMID M1 will be a good replacement, as I *neeed* a mpg readout.

[Matt Timion]

Upon further reading it appears that the SuperMID m-1 is made for the prius. I'd be interested in knowing how it can be converted to an obd1 honda car such as yours, as all of the posts I've read indicate that the program is written based on Prius constants (fuel pressure, etc.)

Maybe I can still coax flatland2d into making a mpg display.

[krousdb]

Originally Posted by Matt Timion

Upon further reading it appears that the SuperMID m-1 is made for the prius. I'd be interested in knowing how it can be converted to an obd1 honda car such as yours, as all of the posts I've read indicate that the program is written based on Prius constants (fuel pressure, etc.)

Maybe I can still coax flatland2d into making a mpg display.

Matt,
There are two calibration parameters, one for fuel and one for speed. Calibrating the speedo/odo is as simple as going for a drive on the highway and counting mile posts. Just scale the distance parameter to calibrate. For the fuel, Just run a tank through and compare what the computer says to how many gallons you pumped. Then scale the fuel parameter. This is the same way that the oztrip works too.

[Matt Timion]

How much does one cost? Where can i order it?

[krousdb]

Originally Posted by Matt Timion

How much does one cost? Where can i order it?

I'm not sure if he is selling them yet. I will check.

[GasSavers_DaX]

Originally Posted by krousdb

as simple as going for a drive on the highway and counting mile posts.

I've often been curious how accurate this is. Does anyone know the precision of mile posts? Is it 1 foot, 10 feet, 100 feet?

[krousdb]

Originally Posted by SVOboy

Calibrate you speedometer and then check it out with a stop watch,

I am also very interested in this, need to buy a damn DMM so I can do your set up first though. Inaaccurate NJ pumping is killing me.

I have found that mile posts are very accurate over long distances. I have tested this in many states on many interstate highways and have always gotten very close results with the same car. I have tested the Prius on 100 mile stretches of the PA turnpike, OH turnpike, New York, Indy Turnpike and some state routes in the Carolinas. Sure, if you do a test for 10 miles you could be off because there is an obsticle where the marker post should be so they move it a few feet. But over 100 miles or even 50 miles, over many different roads, my Prius odo would show within +/- 0.2% of the mile posts. I just do it as a habit on long drives. Something to keep me from falling asleep.

Now the speedo thing might not be quite as accurate. First, don't necessarily assume that the speedo accuracy is equal to the odo accuracy. For digital speed readouts like prius, both use the same speed signal and display digitally so they should be the same. But with analog speedo/odo like my del sol, because there are two analog devices that use a common speed signal, you have some error that could occur. The needle could hang a little or be heavier from one car to the next. I have found that with the Outback and the del Sol, the speedo is lower than the odo, by about 1 MPH. Probably err to the low side for legal reasons.

I use the stopwatch method that you suggested for speedo calibration but it is much more difficult because you have to keep it on 60 and cruise ain't perfect. If you have hills or traffic, you are likely not to maintain 60 for very long. I have a 28 mile of flat state route in SC that I test speedos on. Perfectly flat and no traffic so cruise can give good results. It will be hard to test the del Sol down there. No cruise and it's hard to get the family of 4, a dog and vacation gear all in the del Sol.

The other method of speedo calibration is to drive by one of those speed signs that they place out every once in awhile to warn people to slow down. Problem with those is that they seem to be off by quite a bit.


I'm rambling now.....

[Matt Timion]

FYI, your del sol uses a digital VSS, so you can easily switch to a digital speedometer if you want to.

[Matt Timion]

Just received an email from Yoshi. He is saying that he might be able to assemble one for me after we find out how it works in your Del Sol.