O.K. I hooked up my VSS output wire from the Lt1 PCM to what I believe is the input for the gauge cluster in my 87 T/A for the speedo. The speedo doesn't work at all. Now my question is, is it because the original speedo needs a different type of input? If so, what kind? Any help would be greatly appreciated. I swapped in a 145MPH speedo and I want to see the needle sweep past that number

 

The input for the speedo is different but not sure what you need to convert it.. I switched all my dash gauges to autometer in order to get their nice 5in electronic speedo.. sorry can't help you more.. try TexasLT1 or Matt89rs.. they should know..

 

J...I just left you a tip that you may already know in another thread. Anyway...how about a pic of the new gauges...that might be a better way to go.

 

this is a pic of the overall setup.. It is installed and all works but didn't have my camera with me today.. probably get some pics tomorrow or Tuesday when the car is on the road..

Saw the tip, posted a reply, already there I am going with a ram air setup, though that decision cam after I had already modded the drivers side tray for a slp intake.. oh well.

 

Your best bet is to use the VSS that came with your 87. and rewire the whole thing like it was before.

As per the wiring, I have no clue how to do it since I use a mecanical speedo.

 

I never connected the VSS to the PCM, just left the wiring for that as it is stock. Haven't had any problems but will probably go ahead and hook it up correctly this summer. Only thing I'm concerned about is having a speed limiter all of a sudden, don't know if my PCM has one or not.

 

The PCM can have one depending on how the car that it came from was optioned. If it was in a car with a 110MPH speedo for example and a particular set of tires if I'm not mistaken. If the VSS is not connected to the LT1 PCM, it can not properly adjust the way the motor runs with load which could hurt performance and probably will hurt at the emissions testing facility. That is what I have come up with from the research so far. I just ordered a Dakota Digital box and will try that out when it comes in. Another option I was thinking about was sending the speedo out to one of those places that restores them and have it modified. I'll have to look into that also.

 

Well...I figured it out. While mounting my PCM in the stock location, I came accross the buffer from the original trans. I unplugged it and hooked up the output from the PCM for the VSS and the speedo now works great. Unfortunately, I wasted money on the Dakota Digital box. If anyone needs one, let me know