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Speedometer

4X4HIGH

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Ok, being's there have been a couple posts up lately about others redoing their gauges and since it's been on my "to do" list for awhile now it has inspired me to possibly step forward and start planning my gauges. In doing so I need to know what it's going to take for me to install a 5" speedo and still retain the VSS. I think i'm going to need to purchase one of the cable driven VSS units then wire it into my ECM? Someone please correct me if i'm wrong. I don't know if there's a way to reuse the factory one since it plugs into the factory speedo.

Also need to know how to go about hooking up my speedo cable to an Autometer 3994 that uses a 5/8" x 18 threaded cable. Iis there an adapter available to go from my push on style cable to a threaded fitting?
 
Scott, I am having to go way back for this one, but VDO used to make an adapter that converted the push on to the screw on cable.
I'm pretty sure it was VDO part no. 200203, and you could find them at Summit.
But, they did not list them in the online catalog. You had to call.
Its been a few years, but its cheaper than a custom cable, so its worth a call.

Plus, check this outfit out. They have all kinds of strange stuff.
They have the adapter that lets you use a cable and outputs VSS signals.
They even have a box that apparently has some kind of stepper motor inside that takes the VSS signal and uses it to spin a cable.

http://www.transmissioncenter.net/speedometer_calibration_______va.htm

Hope this helps, or even makes sense. Its 2:30 in the morning, and I'm up with my leg hurting and nothing better to do than bug folks on the forum......
 
I did see that VDO offers an adapter for push on cable but it is for Chrysler applications and is different than GM push on style. I guess i could always just replace my existing push on/thread on cable with a thread on/thread on and then figure out which pulse adapter I would need to keep my ECM happy. I think I found the correct one at www.Jagsthatrun.com it should be the 2PRS as it says for "The two-pulse square wave unit for all passenger car TBI installations, all computer controlled carbureted engines, and 1985–1989 TPI engines. 7/8–18 thread, .104" square drive."
 
Huh, well I was hoping I had something you could use.

I remember that part as fitting a late 60s early 70s Chevelle, but I may be wrong.
No more sleep than I am running on, I'm lucky if its a car and not a boat or gun I'm remembering working on.

But, good news, the bottom just fell out here. It is raining like a cow p*ssing on a flat rock.

I am going to turn up the outside camera sound, and try to sleep.
Rain always puts me to sleep unless I'm out in it.
 
Scott iirc that 2PRS should be the right one from the brief research i was doing over at Jags...

as to the speedo adapters... i use the one you are talking about on my 5" mechanical, clip-in to threaded.. mine was an autometer product.. came on one of those shrunkwrap cardboard packages... i seem to remember someone saying they wheren't being made anymore.. could be, as mine is probably 15 yrs old or more... i'll see about digging a part # off it today for ya...
 
well, the good news is the adapter was sitting 5' away from me on the back of the speedo on my shelf


allright018.jpg





the bad news is, it has no part # on it




allright019.jpg
 
hmm scribed, this is the reason my speedo hasn't been hooked up since I bought it...
 
That looks like the one I remember. Except it was not as blurry....:D

Pretty sure mine came from Summit, but it may have been discontinued then, since we had to call and ask.

This was about 8 years ago.

My notes show that VDO part number, but thats all. I usually have more info than that, but not this time for some reason.
 
starting to think that adapter is like gold... last time it came up in here, and i mentioned it, i don't know if anyone ever found one available...

I'm like one of those "diehard carb guy till I die" types when it comes to my AM mechanical speedo... I've had that thing forever and am comfortable with it...... heck, i've never even owned a vehicle with an elec speedo... I'm sure it's a sweet way to go in this day and age... I just have a hard time letting go sometimes... :wink1:

thank god I embraced FI! :haha:
 
Hey, these days, I'm just glad it looked blurry to someone else.....
 
This is the only speedo adapter I could find. It is a VDO piece and says it is a Chrysler kit and doesn't even look like yours Ryoken.

speedo adapter.jpg
 
I may be mistaken, but when I was trying to find a custom length cable I remember seeing cables with 7/8? and 5/8. Might take a trip to the parts store and browse thru the paper catalogs.
 
This is the only speedo adapter I could find. It is a VDO piece and says it is a Chrysler kit and doesn't even look like yours Ryoken.

the cursory looking around i just did Scott, i can't find a listing for it anywhere... it may have been discontinued... I saw the VDO one... might be worth a quick jingle to AM to verify...
 
I may be mistaken, but when I was trying to find a custom length cable I remember seeing cables with 7/8? and 5/8. Might take a trip to the parts store and browse thru the paper catalogs.

The 5/8" thread is for the speedo end and the 7/8" thread is where it threads onto the transmission/t-case.
 
the cursory looking around i just did Scott, i can't find a listing for it anywhere... it may have been discontinued... I saw the VDO one... might be worth a quick jingle to AM to verify...

I've already contacted Autometer and they said to just have a new cable made. At this point I might just go with one of the analog electric speedos instead and then buy the correct VSS to make the speedo work and hopefully it can also be used for the ECM at the same time. I have to check into a little more. The one nice thing about the electric speedo is that they are programmable so if I ever change tire size or gearing I can recalibrate myself very easily.
 
i should have gone electric speedo when i did my gauges. Comepletely tuneable and you should be able to plug an autometer into your existing vss.
 
i should have gone electric speedo when i did my gauges. Comepletely tuneable and you should be able to plug an autometer into your existing vss.


It's not that easy. Remember that up until 1989 the factory speedometers used a cable and the VSS plugged into the back of the speedo (not the cable driven part) so once you remove the factory speedometer you also lose the pick-up for the VSS since there is no longer a cable spinning the speedometer in order for the hall effect VSS to work. No matter if I choose to stay with a mechanical or electric speedo I will have to also purchase a cable driven VSS and install it at the t-case and then run the wires up to an electric speedo and also to the existing wires from the factory VSS (not even sure if one cable driven aftermarket VSS can be used for multiple things). Cruise control uses VSS and the VSS also sends info to the ECM to help with the IAC motor.
 
It's not that easy. Remember that up until 1989 the factory speedometers used a cable and the VSS plugged into the back of the speedo (not the cable driven part) so once you remove the factory speedometer you also lose the pick-up for the VSS since there is no longer a cable spinning the speedometer in order for the hall effect VSS to work. No matter if I choose to stay with a mechanical or electric speedo I will have to also purchase a cable driven VSS and install it at the t-case and then run the wires up to an electric speedo and also to the existing wires from the factory VSS (not even sure if one cable driven aftermarket VSS can be used for multiple things). Cruise control uses VSS and the VSS also sends info to the ECM to help with the IAC motor.

so would this part solve the problem?

http://www.summitracing.com/parts/ATM-5291/
 

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