I have an 85 T/A with the 85 mph speedo and want to change to a higher speed, but all seem to be in 86-up with electronics. Is there an easy way to upgrade my cable driven one so that the speedo reflects the true personality of the car? Hell, my 85 Dodge minivan has a speedo up to 120, but there's no way in hell it would ever get there...why have such a lame-o speedo in a performance vehicle anyway??? Thanks in advance for any information y'all feel like giving!

 

From what I have heard there was government mandates that only allowed up to 85mph spedos from the early/mid 70's thru about 86.

Going to an electronic speedo I really do not know how you would do that, although there are those who have done it.

it might be just a matter of getting the sender for the transmission, and running some wires and the dash, might need the ECM, in which case you would need to re-wire your engine. (85 used a different ECM than 86-89 and 90-92)

You might actually try the TPI board, or the PROM Burning boards.

Its been a while but:
There is another possibility that inside your speedometer there is a drum that connects to your speedo needle. Around that drum there are 2 magnets that spin. The closer the magnets are to the drum the more of a reaction it has to the drum, the furtherr they are from the drum the less of a reaction.

There is a possiblity that if you were to spread the magnets from the drum that you could calebrate the magnets to read at a different ratio and make your own 140 or even 200mph speedometer.

Be warned tho, the magnets are on a magnesium or aluminum or zink casting, and they might easily break off, so do your experiments on an extra speedo...

Of course if you feel like being Franknstine you might be able to get a cable cluster from another vehicle like a buick, that does not use the same range as our speedos, consider that in the 80's there was alot of speedos that only used a range of 90° to go from 0-85 mph. Our speedos typically seem to have a range of 270° in which you would effectivly have a 255Mph Speedo.

Its worth a shot.

think about it. plan it, and do it...

hope that helps

John

 

Go to www.markscustomkits.com He's a guy that does TA restoration stuff and he converts Trans-AM's into KITT replicas. On the site he has a total digital electronics package to convert all your guages to digital and still keep the stock dash pad and guage facing. You might want to email them if you want just the speedometer. The whole digital dash electronics package is pretty expensive but it shouldn't be limited to 85MPH.

 

I have everything you need to convert, including the cluster.
I've got the VSS Sender, VSS buffer box, wiring, and the gauge cluster. Actually, I am selling the entire dash with wiring and switches.
Give me $300 + shipping and you can have everything or $150 for the cluster and VSS electronics.
I am going with a complete 4th gen dash/electronics setup so I need to sell my 3rd gen setup to help pay for the 4th gen stuff.
Here is a pic of my cluster,


This is going to be fun. I plan on re-doing almost all of the cars wiring, that way I know exactly where each wire goes and what it does.

 

Zephyr, dude, been admiring your work for a while...:hail: It would be an honor to buy your setup, but I need to get some positive cash flow first, should have it very soon. Don't hold it on my account, if you have a buyer, sell! But I'll check with you as soon as I get the funds. Would you know what a pain it will be to switch over to the VSS system from the cable driven old school? Should just be a switch and a sensor mounted at the tailshaft of the tranny, right? (basically, I know there's more to it than that) Also, thanks to everyone who is trying to help me with this...it IS appreciated.

 

Ya, it shouldn't be all that hard.
Change the VSS Sender in the tranny, run the wire from the Sender to the VSS Buffer and then run the wires from the buffer to the cluster.

Running the wires From the buffer to the cluster might be the hardest to run since it is behind the dash.
I'll probably still have it when you get the cash, so just shoot me an email, zepher_ws6@***.net

Later,

 

Zepher, how is that motor coming along? Did you sell the intake?

 

It's coming along.
Which intake are you referring to? The SLP? the LT1? the TPI?
I sold them all.

 

No, i thought you had a LT4, or was it powdercoated red? So if you sold all of them what are you going to run, a carb? good luck with the project!

 

I have the LT4 intake and LT4 heads, so I sold the LT1 heads and intake.

 

Oh, alright! I thought you had either one, or the other, not both! good luck with it.

 

Thanks,
hopefully I'll be able to get the motor back together and into the car soon.