KMPH to MPH Speedometer Converter?

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napphappy
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KMPH to MPH Speedometer Converter?

Post by napphappy »

I just bought a JDM gauge cluster. It uses the VSS for the speedo. I know you can buy electronic converters. My question is what would it take to make one? It cant be that hard right.

The conversion factor is 0.621371192

Or does anyone know of a schematic for one online already.
1997 White BG Ltd 5MT, EJ22T with Wiescos, EJ20R Heads, Two large dents R.I.P
1995 Impreza EJ22T DOHC Hydra EMS, 20g, EWG, 3in APS TBE, AWIC
vrg3
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Post by vrg3 »

You're talking about for your touring wagon?

Our stock setup has a spinning cable going from the transmission to the speedometer, and a VSS built into the speedometer.

To use an electronic speedometer at all, you'll need to get a later-model VSS that threads into the transmission and wire it into the speedometer and the ECU.

I don't know if this is even a possibility (since it might be impractical or ugly), but have you considered transplanting just the face of the stock speedometer gauge to your new cluster? Or repainting that part of the cluster?
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
napphappy
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Joined: Fri Jun 03, 2005 12:57 am
Location: Gig Harbor, WA

Post by napphappy »

No its for the outback. It already uses an electronic VSS for the speedo. I just need to slow the signal down so that it reads MPH instead of KMPH.

I thought about switch the dials, but it wouldnt line up.
1997 White BG Ltd 5MT, EJ22T with Wiescos, EJ20R Heads, Two large dents R.I.P
1995 Impreza EJ22T DOHC Hydra EMS, 20g, EWG, 3in APS TBE, AWIC
vrg3
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Post by vrg3 »

Glad I asked. You should probably specify which car when you ask questions about the Outback here.

Do you think you'd be willing to tolerate the error produced by using a ratio of 0.5 instead of 0.62? Cuz dividing the frequency by two would be dead easy to do.
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
napphappy
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Location: Gig Harbor, WA

Post by napphappy »

That would be over 10mph off on the freeway. I dont know.
How hard would it be to make it work right.
1997 White BG Ltd 5MT, EJ22T with Wiescos, EJ20R Heads, Two large dents R.I.P
1995 Impreza EJ22T DOHC Hydra EMS, 20g, EWG, 3in APS TBE, AWIC
vrg3
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Post by vrg3 »

Well, give me a little while to think about it. I think reducing the frequency to 60% shouldn't be too hard. I'm thinking a CD4017 decade counter and a 74F38 open-collector buffer might do the trick. Email me at vikashgoel at gmail dot com if I don't reply within a week.
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
napphappy
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Post by napphappy »

cool thanks
1997 White BG Ltd 5MT, EJ22T with Wiescos, EJ20R Heads, Two large dents R.I.P
1995 Impreza EJ22T DOHC Hydra EMS, 20g, EWG, 3in APS TBE, AWIC
scuzzy
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Post by scuzzy »

napphappy wrote:cool thanks
go ahead and draft the email, yer gunna need it :-D
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vrg3
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Post by vrg3 »

...yeah... :oops:
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
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