SuperMID M1, MPG Computer

[krousdb]

Originally Posted by 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.

Yes,
I heard the same from him today. He also said.....

Originally Posted by Yoshi

The Toyota Tech Manual says the injector spec is between 36 to 46cc
in 15 sec, which means about 164cc/min. However, my Prius measurement
result is 222cc. The default fuel parameter is 13515 to meet Prius.
Anyway, the fuel parameter can be set about plus/minus 50% of above.
I believe you'll be able to find the best parameter using the current
+/- 50% range.

Your 240cc is just a spec value, and I believe the actual may be varied.
Good solution is that drive a tank, then fill up.
Calc the real mileage, then compare to the displayed value.
Then, adjust the parameter referring to the bottom of attached PDF file
which was sent to you last summer.
Anyway, I believe you don't need an absolute mileage value, but
a relative value comparing your driving styles will be enough. :-)

Regarding to distance parameter, the default 2572 value should
be right on if you wear a standard size of tires. It's the industrial
standard.

I have a pdf file that explains the features and calibration parameters. I just don't know how to post it.

[krousdb]

http://img223.imageshack.us/img223/1883/m1menueng7of.jpg

SuperMID Functions and calibration detail. I had to convert to jpeg before the service would accept it. The pdf is much clearer.

[krousdb]

The SuperMID set up for the Prius has a distance parameter value of 2572. If you divide by 3, you get 857. The Prius OEM tire has 855 revs per mile. So my guess is that the Prius speed sensor sends out 3 pulses per revolution. Can anyone tell me if the Honda speed sensors have the same 3 pulses per revolution? If so, since my tires are 840 revs per mile, I will set the parameter to 2520.

[GasSavers_DaX]

Originally Posted by krousdb

The SuperMID set up for the Prius has a distance parameter value of 2572. If you divide by 3, you get 857. The Prius OEM tire has 855 revs per mile. So my guess is that the Prius speed sensor sends out 3 pulses per revolution. Can anyone tell me if the Honda speed sensors have the same 3 pulses per revolution? If so, since my tires are 840 revs per mile, I will set the parameter to 2520.

In the OBD training manuals I sent you, I think this is outlined.

[GasSavers_Yoshi]

Hello all from Japan.
Thank you for your interest in my SuperMID.

Originally Posted by krousdb

The SuperMID set up for the Prius has a distance parameter value of 2572. If you divide by 3, you get 857. The Prius OEM tire has 855 revs per mile. So my guess is that the Prius speed sensor sends out 3 pulses per revolution. Can anyone tell me if the Honda speed sensors have the same 3 pulses per revolution? If so, since my tires are 840 revs per mile, I will set the parameter to 2520.

The revolution standard is some what different.
Let's imagine an old mechanical speedometer driven by wire cable.
The industrial standard is 637 revolution for 1km drive.
Hopefully, Honda uses the same standard.

Prius sends 4 pulses per the cabe revolution, which means about 39.25 cm/pulse. ( 100,000 cm / (637 * 4 ) )
The SuperMID M-1 wants 0.01km(10m) resolution, then I programmed it as follows...
A 16bit register accumulates "some value" until it overflowed(value becomes 65536 or over), then increment the 10m memory data. We need 25.48 pulses for 10m drive. ( 1000 cm / 39.25 cm )
The "some value" is 65536 / 25.48 = 2572.

So, please forget to compare the tire sizes between Prius and del sol.
Please compare between standard and your tire on del sol, or it is better to calibrate the display value using your favorite miles-post method.

Regards,
Yoshi

[krousdb]

Originally Posted by Yoshi

Hello all from Japan.
Thank you for your interest in my SuperMID.

The revolution standard is some what different.
Let's imagine an old mechanical speedometer driven by wire cable.
The industrial standard is 637 revolution for 1km drive.
Hopefully, Honda uses the same standard.

Prius sends 4 pulses per the cabe revolution, which means about 39.25 cm/pulse. ( 100,000 cm / (637 * 4 ) )
The SuperMID M-1 wants 0.01km(10m) resolution, then I programmed it as follows...
A 16bit register accumulates "some value" until it overflowed(value becomes 65536 or over), then increment the 10m memory data. We need 25.48 pulses for 10m drive. ( 1000 cm / 39.25 cm )
The "some value" is 65536 / 25.48 = 2572.

So, please forget to compare the tire sizes between Prius and del sol.
Please compare between standard and your tire on del sol, or it is better to calibrate the display value using your favorite miles-post method.

Regards,
Yoshi

Yoshi, Glad to see you here! I will probably leave the default value and change it after 50 miles on my trip odometer. I can get it close anyway. Then I will do the milepost calibration. I can hardly wait!

[Matt Timion]

mile post calibration may be the best bet for me. My tires are not the stock size, so my odometer/speedometer is not 100% accurate, although it is within error.

Maybe another possible solution is to drive a certain distance with a handheld GPS unit that is accurate within a few feet and then use the distance displayed there.

[GasSavers_DaX]

Whichever method you use [milepost or GPS], be sure to keep in mind that the more markers you pass, the more accurate your results due to the law of averaging.

[Matt Timion]

Originally Posted by DaX

Whichever method you use [milepost or GPS], be sure to keep in mind that the more markers you pass, the more accurate your results due to the law of averaging.

Very true. I might have access to GPS equipment soon that is made to have accuracy of .05 feet, which is less than an inch. If there is the right software to calculate distance and speed, then I'll be set for calibration.

[krousdb]

Good from Yoshi today. He said that he hoped to have the M1 finished over the weekend and send it to me on Monday. It should be here 6-10 after that. I can't wait!