Electronic Speedo Hook up

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5.7 hemi

5.7 hemi

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Since I have found out that wire coming out of the harness for the electronic speedo signal from hotwireauto isn't truly a speed signal I have decided to go with a gps sender, intelletronix.com for a few reasons.

1. My speedo counts mileage with the engine running, doesnt matter if the car is moving.
2. Speedo will jump if goosed when in park and neutral.
3. This is a simple 3-4 wire hook up and does not care what tire size or gearing I have.
4. This was not nearly as pricey as all the others I looked at.

I will post up how it goes in and how quick it is to registor and the accuracy when I get it, which should be this afternoon. So anybody that has a wiring harness and using the 545rfe trans, take a look.
 
Well I got it wired up and it works. Although it is slow from a stop, it does catch up really quick. I'll have to call them on monday and maybe the gauge manufacturer. I have it set for 8k and the gauge also, so maybe I missed something but I cant see what it could be since it's only 3 wires to hook up.
 
abodyjoe said:
Would have gone gps also if I knew then what I know now.
Click to expand...

What is it thst you know now? I've seen your dash/ wiring thread and it is very informative.

Are you confirming 5.7 Hemis' assertion that the electric pickup is not that great? I never even thought of doing gps, but now intrigued

-chris
 
Update....called the gps techline and the guy was stumped about it not working properly and said that it should not have any lag from a stop to go. He suggested I call the gauge techline and see what they got to say and to call him back so he can put it in his database for future use, sounded good to me. Called the gauge techline and I think we have grandslam. He said that I need to calibrate gauge with the sending wire from the gps and not the harness, and it should be good as both are 8000ppm. I calibrated the speedo with the harness wire then switched to the gps, dohhh!!! I'll recalibrate as instructed and post what happens, after I fix my hot lead to the fuel pump (shorted to the bottom of the trunk pan) another dohhh!!
 
CudaChris67 said:
What is it thst you know now? I've seen your dash/ wiring thread and it is very informative.

Are you confirming 5.7 Hemis' assertion that the electric pickup is not that great? I never even thought of doing gps, but now intrigued

-chris
Click to expand...

when it first went in it used to jump all over the place while driving. called autometer and they tell me that the power source has to be all alone.. directions show something different but ok. did that and the same thing. called them again. they said the sensor wire should have some fancy shield on it.. they say that to me like i should have known.. well i never used an electronic speedo and the directions say nothing about it. i said screw that. i'm not pulling that wire back in the car and all so i left it.. speedo seems to have calmed down some now. doesn't jump 10 mpg anymore. stays pretty steady. but sitting in neutral and revving the motor the speedo will go up so it is still getting interference from the electrical system somewhere. just a pain in the ***. with a gps unit i wouldn't have to worry about running the wires out the firewall and down to the trans where is supposed to be picking all this interference up.
 
It works!!! Now the down side, it takes to long to registor speed. I could be a half mile down the road and it finally reacts and though it shows the speed (which I believe to be accurate) its still not right and mileage will also be not true. So another call is in order.
 
I have a GPS speedo app on my phone that I use, and it is pretty good, but when I am climbing speed fast it can't keep up. That is the main reason I am not going with a GPS speedo and am going with a high quality electronic one instead.
 
Just curious, your GPS has acquired satellites before going right? If not you wont get a reading until they reach coincidence and sync.
Also the microprocessor update on the phone will affect update speed. Sorry if this is too lame but from what I am hearing iit shounds possible'.
Otherwise I retreat into the night!
cheers
 
Why is something that is so simple, so hard?
 
Good question Tin, and I have the answer. The hot rod gods hate us, lol!! I'm gonna give the gps sender another try and if it doesn't work faster then I'll go back to the harness sending wire and move on.
 
5.7 hemi said:
Good question Tin, and I have the answer. The hot rod gods hate us, lol!! I'm gonna give the gps sender another try and if it doesn't work faster then I'll go back to the harness sending wire and move on.
Click to expand...

I just got in my Autometer unit, I'll see if it works any better..
 
I have Speedhut electronic gauges, but do not have the car road ready to test to tell you how it works. According to their instructions the speedometer is designed to work with any waveform from 2Volts - 200Volts. Pulses per mile from 500-250,000 pulses per mile.

If I have problems with getting stable readings I will likely try drilling and tapping a hole along the same gear and use their universal electronic sender.
http://www.speedhut.com/product_detail-AUTO_NUMBER-788.htm
Has anyone tried or considered this option to get a better signal?
 
If I have problems with getting stable readings I will likely try drilling and tapping a hole along the same gear and use their universal electronic sender.

Me no understand.
 
Nevermind Boden, I figured it out.
 
You could try wiring your speedo directly to the speed sensor on the trans and bypass the computer all together.
I also twist a wire around the speed sensor wire and ground it. It helps sheild the wire from outside interference.
 
abodyjoe said:
they said the sensor wire should have some fancy shield on it.. they say that to me like i should have known.. .
Click to expand...

"Faraday shield?"

One thing you guys might try is shielded wire with the shield grounded ONLY at one end, INSULATED at the other end.

Revhendo said:
I also twist a wire around the speed sensor wire and ground it. It helps sheild the wire from outside interference.
Click to expand...

This is probably similar, and is recommended in other low voltage schemes such as building phone wiring. You simply ground the termination end of "unused pairs" of a cable and those then become a shield.
 
I think I like the idea of a gps speedo. Seems that it would be fairly accurate where most important, when your cruising down the road and simply want to be within ten miles an hour of the speed limit so you don't get a ticket.

If it lags a bit who cares?

Or are you guys trying to do time trials in your front yard? :)

:burnout:

Regards,

Joe Dokes
 
A bike I had a while back had an electric speedo, was very jumpy until I shielded the wire.
 
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