Fuel Economy Gauge?

[Bubba Bob]

Alrighty,

First let me say I drive an 85' Ford F150 w/ the 302 V8. The truck is used as a truck so I cant just trade it in on a compact car, I would however like to improve its gas milage. I would love a gas milage gauge like the new Ford F-Super Duties have, but I cant seem to find one.

That is, untill I found this site...

I have some questions about this infamous "Supermid".

1) Exactly how does this little gadget work? How does it calculate FE and how accurate is it?

2) What do I do about my mechanical speed sensor?

Thank Yall for the Replies.

[SVOboy]

1) VSS and injector pulse width signal. Very accurate.

2) Add a digital one or you're likely out of luck!

Welcome!

[Bubba Bob]

Thank you for the quick reply!

Where does it get the injector pulse from?

Is this digital VSS something I can buy anywhere? **looks for O'Reilly's catalog**

[SVOboy]

I'm guessing the 85 is carbbed? The pulse width comes from one of the injector control wires.

I don't think it's too easy to hook up a digital vss from scratch...I've heard some things about getting a magnetic thing to sit on the axel and count rotations, but Iono for sure...someone else will though.

[Bill in Houston]

I think it woulda been TBI. My 84 tbird with 302 was TBI. So, that is good news.

[Bubba Bob]

Yup, it's fuel injected.

The more I search this forum, the more I think it's not worth the trouble... Looks like the VSS is a major problem...

[basjoos]

If your engine is carburated rather than fuel injected, its going to be a bit of a job to produce the equivalent of an injector pulse from it. You would have to install a paddlewheel flowmeter in the fuel line feeding the carb to produce a pulse frequency proportional to the fuel flow, then use a frequency to duty cycle convertor to convert increasing frequency to a higher duty cycle. You would need to do some research to determine your range of fuel flows and select a flowmeter that would give an appropriate range of pulse frequencies and then find a freq to DC convertor that could produce an square wave pulse mimicking the square wave pulse that the SuperMID is set up to receive. You would need to contact Yoshi to for the specs on the range of VSS pulses. As far as I know this hasn't been done, but it would be an interesting project for someone with a bit of electronics background.

[Bubba Bob]

ALrighty, I found a cheap eletric VSS. Its one that mounts magnets on the axle (I assume). It comes with four magnets. (judging by the picture) Is this what I need?

Link:

http://store.summitracing.com/partde...5&autoview=sku

[brucepick]

For a truck, I'd say aero mods would be real good.
Along with good driving, like moderate speeds and P&G technique, and the usual vehicle maintenance and tire pressure as high as is safe.

My old Volvo is not very aerodynamic and I feel a big change after my recent aero work. Better mpg #s also. If you have something with low drag like a Geo or a Prius you might need a degree in aerodynamics to improve it. But with a rolling box like mine, or a truck, I think you can really help yourself with aero mods if you do some research. I'd look here under the Aerodynamics Discussion and in wikipedia under Automotive Aerodynamics. Watch out for the race car stuff. They often want to create down pressure for traction. You don't need that but you do need smooth ar flow.

[Matt Timion]

Originally Posted by Bubba Bob

Yup, it's fuel injected.

The more I search this forum, the more I think it's not worth the trouble... Looks like the VSS is a major problem...

This isn't true. Yoshi (the inventor) found a magnetic sensor that you can attach to your axle in lieu of an electronic VSS that he said will work with the SuperMID.

Hopefully he can chime in here.

[Bubba Bob]

Originally Posted by Matt Timion

This isn't true. Yoshi (the inventor) found a magnetic sensor that you can attach to your axle in lieu of an electronic VSS that he said will work with the SuperMID.

Hopefully he can chime in here.

I think I found what you speak of. I read on this forum somewhere (cant find it now) that I need 4 pulses for every tire rotation. Is this true?

Also, can the Supermid be calibrated for different tire sizes?



Areodynamics is a problem for this truck for sure. Im thinking about taking the passenger side mirror off, as well as the roll bars off. Leaving the tailgate down does nothing, correct? A big drag for me is my 5 foot CB antenna. Its staying but I do have a spare 4 footer I might replace it with if I start doing alot of highway miles.

[Matt Timion]

Originally Posted by Bubba Bob

I think I found what you speak of. I read on this forum somewhere (cant find it now) that I need 4 pulses for every tire rotation. Is this true?

Also, can the Supermid be calibrated for different tire sizes?



Areodynamics is a problem for this truck for sure. Im thinking about taking the passenger side mirror off, as well as the roll bars off. Leaving the tailgate down does nothing, correct? A big drag for me is my 5 foot CB antenna. Its staying but I do have a spare 4 footer I might replace it with if I start doing alot of highway miles.

I will send Yoshi a message and tell him to answer your questions.

[Bubba Bob]

Originally Posted by Matt Timion

I will send Yoshi a message and tell him to answer your questions.

Hey Matt, thanks but I just fired one off to him,

[Yoshi]

Hi Bubba and all,
Thank you for your interest in my SuperMID and PM.

* fuel usage measurement
Please note that there are a lot of types fuel injection system.
http://en.wikipedia.org/wiki/Fuel_injection
The SuperMID measures the pulse width signal of one of fuel injectors.

- MPFI with high impedance injector works best.
- MPFI with low impedance injector needs special circuit.
http://www.gassavers.org/showpost.ph...4&postcount=16
- TBI with a single injector works good.
http://www3.telus.net/metro/mid.htm
- TBI with dual injectors does not work since SuperMID has only one onput.
(I think the each injector has different characteristic.)
- Continuous injection like Bosch's K-Jetronic does not work.
- Electric carburetor does not work.
- Diesel injectors does not work, I think.

Originally Posted by Bubba Bob

ALrighty, I found a cheap eletric VSS. Its one that mounts magnets on the axle (I assume). It comes with four magnets. (judging by the picture) Is this what I need?

Link:

http://store.summitracing.com/partde...5&autoview=sku

I can't find any detail specifications about it, and can't judge whether it works or not.

* distance measurement
- recent Toyota and Honda vehicles have digital clean VSS signal.
- The standard is 4 pulses/rev of speedometer cable or 2548 pulses/km, or sometimes 4000 pulses/mile.
- We need special filter circuit for a mechanical switch VSS, which produces a chattering and noisy pulse, like installed on landspeed's Nissan.
- For those which does not have any VSS, I can supply mechanical switch VSS for Toyota, Nissan, Mitsubishi, Mazda and Daihatsu with the filter circuit.
http://www.gassavers.org/showpost.ph...9&postcount=17

Regards,
Yoshi

[caprice]

Since you have TBI, you should have an electronic VSS. And just because your speedometer is mechanical, you still may have a VSS. My Caprice had a mechanical spinning cable that want to the speedometer, but it has a pickup that reads off the speedometer is the VSS.

[Bubba Bob]

Hmmm, I dont remember ever seeing threads on my VSS line. Ill check tomorow.

Do you have any info on that magnetic setup Matt mentioned?

[Bubba Bob]

Originally Posted by caprice

Since you have TBI, you should have an electronic VSS. And just because your speedometer is mechanical, you still may have a VSS. My Caprice had a mechanical spinning cable that want to the speedometer, but it has a pickup that reads off the speedometer is the VSS.

THanks Caprice. Ill look into that.

[Yoshi]

Originally Posted by Bubba Bob

Do you have any info on that magnetic setup Matt mentioned?

I explained it on the post...
http://www.gassavers.org/showpost.ph...9&postcount=17
It is 4 pulses/rev and works with the SuperMID.
I don't know what kind of connecting thread standard Ford uses.

Yoshi

[Bubba Bob]

Originally Posted by Yoshi

I explained it on the post...
http://www.gassavers.org/showpost.ph...9&postcount=17
It is 4 pulses/rev and works with the SuperMID.
I don't know what kind of connecting thread standard Ford uses.

Yoshi

Ah, didnt realize that was the magnetic setup. No, that deff. wont work. I was just told my truck has an electric VSS for the computer. Im about to look for that.

If my truck does have the electric VSS, will it even work since the supermid is designed for 2 times as many pulses as what mine probably will give? (according to a source, my should pulse 8000 per mile)