Author Topic: Electronic speedometers  (Read 16888 times)

Offline Rattler12

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Electronic speedometers
« on: December 10, 2015, 12:05:44 pm »
I am restoring an 83 C-10 with a 454 and have swapped in an NV-4500 5 speed. The speedo in the truck is mechanical but the trans does not have a mechanical hookup, only the sensor hookup for electrical speedos. I would like to stay with the stock look of the dash and not go the New Vintage or Dakota digital route. Anyone know of a source for OE electrical speedo replacements. Did the 87's have electrical speedos?  Anyone done this transmission swap into 73-87 and if so how did you handle the issue?

Thanks for any help/advice
Ratller
83 C-10 shorty 454, 5spd, 3:73 posi

Offline werewolfx13

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Re: Electronic speedometers
« Reply #1 on: December 10, 2015, 03:07:05 pm »
87 was still mechanical, or at least mine was.
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Offline Irish_Alley

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Re: Electronic speedometers
« Reply #2 on: December 10, 2015, 05:26:59 pm »
my take on this the nv4500 never came in one of our trucks, even up to 91. i have a electric speedo on my 91 crew cab, but the dracs box (converts the pulses from the trans to another signal that gets sent to the speedo) is touchy and after my cummins swap i still cant figure it out lol.
but you do have this option but at $300 it might not be reasonable and my cell phones gps is a free app thats accurate and you dont have to worry about tire size or ratio calibrations
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Offline Rattler12

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Re: Electronic speedometers
« Reply #3 on: December 10, 2015, 06:02:34 pm »
Yeah, the NV was put in 3/4 and 1T's from 92 through 07. It was also in Dodges and had the mechanical speedo hookup, but the Dodge version had different length/spline count input & output shafts.....thanks for the info. I have the speedo out of an 87 and it has a three wire electrical hook up on the back next to the mechanical that terminates into a light greenish looking connection. What's up with that?
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Offline Irish_Alley

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Re: Electronic speedometers
« Reply #4 on: December 10, 2015, 06:41:47 pm »
i dont want to be giving out bad info. i know with mine the dracs sends the signal to the abs, cruise, speedo and ecm. but i know the dracs wasnt around pre 90ish
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Offline bd

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Re: Electronic speedometers
« Reply #5 on: December 10, 2015, 07:18:49 pm »
...I have the speedo out of an 87 and it has a three wire electrical hook up on the back next to the mechanical that terminates into a light greenish looking connection. What's up with that?

There's an optical sensor at the back of the 1987 speedo head that monitors speedometer cable RPM.  The light green box is a buffer that processes the signal from the optical sensor to provide VSS input to the ECM and Custom Cruise III cruise control.  Essentially, it is the interim VSS before transmission mounted signal generators were used.
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Offline Irish_Alley

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Re: Electronic speedometers
« Reply #6 on: December 10, 2015, 07:38:45 pm »
...I have the speedo out of an 87 and it has a three wire electrical hook up on the back next to the mechanical that terminates into a light greenish looking connection. What's up with that?

There's an optical sensor at the back of the 1987 speedo head that monitors speedometer cable RPM.  The light green box is a buffer that processes the signal from the optical sensor to provide VSS input to the ECM and Custom Cruise III cruise control.  Essentially, it is the interim VSS before transmission mounted signal generators were used.

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Offline Rattler12

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Re: Electronic speedometers
« Reply #7 on: December 10, 2015, 08:53:33 pm »
Looks like I gotta go aftermarket......I bought a Vintage set up that's supposed to be a "direct fit" but it's pretty cheesy and cheaply configured.......for $800 plus. The gauges themselves look pretty much top shelf but the mounting set up is sorely lacking.....anybody used Dakota Digital?  Is it any better?
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Offline big_al273

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Re: Electronic speedometers
« Reply #8 on: December 10, 2015, 11:06:48 pm »
I'm planning on swapping a NV4500 into my truck as well, but i am running a 4x4 and will have my mechanical speedo cable in the stock position on my np-205, have you looked at taking a dodge nv4500 mechanical speedo output too see if it could be put into the gm nv4500?
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Offline travisr1988

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Re: Electronic speedometers
« Reply #9 on: December 11, 2015, 07:43:29 am »
An alternate to new gauges is a converter box, Dakota digital has them. Essentially the electronic input goes to the converter then you run a cable from the box to the gauge.
http://www.dakotadigital.com/index.cfm/page/ptype=product/product_id=886/category_id=-1/mode=prod/prd886.htm
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Offline Rattler12

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Re: Electronic speedometers
« Reply #10 on: December 11, 2015, 08:08:56 am »
Thanks .....that's sounds like the solution 
83 C-10 shorty 454, 5spd, 3:73 posi

Offline zieg85

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Re: Electronic speedometers
« Reply #11 on: December 11, 2015, 09:11:17 am »
What about the speedometer cluster out of the 1991 Suburbans?
Carl 
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Offline bd

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Re: Electronic speedometers
« Reply #12 on: December 11, 2015, 09:56:05 am »
The "73-87 Chevy Trucks" store is a dealer for Dakota Digital.  Email Captkaos at webmaster@73-87chevytrucks.com for availability and pricing of the ECD-100.
Rich
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Offline hatzie

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Re: Electronic speedometers
« Reply #13 on: December 11, 2015, 10:58:39 am »
I had a 4x4 and used an NP208C so I never ran into the VSS to cable problem.

The early 2WD Dodge NV4500 had cable drives.  Not sure how much good it does you.  There are rumors that the early GM units had an un-machined boss for the speedo gear carrier.
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