SuperMID revisited - Page 3

krousdb · 06-09-2006, 03:57 AM

I did some analysis of the fuel and distance parameter ranges and came up with the following guesstimates....

The SuperMID can accommodate tire diameters from 17.0" to 26.7" assuming that your VSS uses the industry standard signal. This works on Toyota and Honda for sure.

The fuel parameter is less straightforward but here goes...

Take your injector size and multiply by the number of injectors that you have. In my case, 240x4= 960. Ben has 190x4=760. From what I have been able to determine given my fuel parameter value, the Prius fuel parameter and the range of acceptable values, I estimate the lower limit is a value of 230 and the upper limit is 1050. Based on that info it seems reasonable that both 3 and 4 cylinder Suzuki clones can be acommodated. All this assumes that fuel system presseres are similar.

Now the interesting question is, can DPFI ot TBI be accommodated? Well, one or two injectors will make the end value lower but I assume the injectors are larger. It may be possible.

And one more thing to consider..... to convert km/L to MPG, you multiply by 2.35. Applying that factor to the upper and lower limits gives a range of 550 to 2450. So in theory more cylinders could be acommodated, up to 10 with 240cc injectors. The average FE would display in MPG but the fuel used would be in no common unit of measure.

And also remember that the instantaneous FE value will be inaccurate if your value is something other than 760 or 960.

I guess the best thing to do would be to get a GasSavers SuperMID and send it around to experiment on different cars. That will be the only way to know for sure.

95metro · 06-09-2006, 06:08 AM

Thankfully everything is okay and there IS a speed sensor in the Metro. I examined wiring diagrams for hours last night (there is so much information available behind that cluster!) and the speed sensor is located in the cluster. A yellow/green wire then sends the signal to the ECU.

Matt Timion · 06-09-2006, 07:59 AM

Quote:

Originally Posted by krousdb

A message from your local SuperMID Technical support geek.....

Nooo Matt. There are two inputs, injuctor pulsewidth and distance. Each one has to be calibrated by adjusting the fuel parameter or the distance parameter.

This seems a bit too complicated for me.

In theory, you can hook it up to one injector wire and the vss. You could then calibrate it on distance (drive 130 miles, etc. and then tell it how far your drove) and fuel (burn through X number of gallons and then tell it how much fuel you used). It could then determine the correct pulse duration for both the VSS and the injector wire. This would be independant of number of cylinders, engine size, tire size, etc.

Mulitplying by four automatically discounts vehicles like the Insight, all 88-91 DPFI hondas, 3 cylinder Geo Metros, etc.

Then again it's important to remember the origins of the SuperMID, which was originally designed to work only for the Prius and not as a universal application.

Gary Palmer · 06-09-2006, 08:24 AM

From the way you are describing the SuperMID, I don't think it would work on the DPFI system, on the Honda's. From what I've read it sounds to me like the Honda uses one of the injector's as the primary and one of the injector's as a supplementary one, for when you have the throttle more open. It sounds like the SuperMID presumes that all of the injector's are open for the same duration.

Do you have any idea what type of a signal is generated for the speed on the Geo?

Matt Timion · 06-09-2006, 08:27 AM

Quote:

Originally Posted by Gary Palmer

From the way you are describing the SuperMID, I don't think it would work on the DPFI system, on the Honda's. From what I've read it sounds to me like the Honda uses one of the injector's as the primary and one of the injector's as a supplementary one, for when you have the throttle more open. It sounds like the SuperMID presumes that all of the injector's are open for the same duration.

This is exactly right. The Honda DPFI system is more or less a carburator with fuel injectors. It fires one injector for all four cylinders under normal conditions. If the SuperMID read this information and then multipled by four it would be equivilant to a 16 cylinder engine (4x4). That's just not going to work.

SVOboy · 06-09-2006, 11:26 AM

Multiplying by four does not make it impossible to run on 3cyl or 1 injector cars, so i don't see what the hang up there is. however, with DPFI, it will not work.

krousdb · 06-09-2006, 01:49 PM

It doesn't matter how many cylinders you have as long as the injector size times the number of injectors falls between 230 and 1050. It should work on 3 cylinders.