I finally got my 6.0 in and we are in the process of tuning it. I need to know where the red connector, terminal 50 grn wire hooks up on my car. The lap top will read the mph but my speedometer does nothing, Has anyone had this problem?

 

Depends on what your car came with originally

82-89 camaros require a cable driver box. Hook it directly to the input wire, then add 12v and ground
90-92 camaros had electric speedos. V6 and TPI cars hook it directly to C207 pin D (GRY). TBI cars hook it to C207 pin K (BRN) and bypass the buffer box by connecting pins C&F

82-86 Firebirds were cable driven, see above
87-89 firebirds were all wired with the buffer box regardless of engine. See above
90-92 firebirds, same as camaros

Theres all you need to know about speedo wiring for LT1/LSx swaps for all 3rd gens. From now on Im going to link this thread instead of typing it out every time

If your gauge does nothing still, check the conversion factor from trans to trans. A forgotten 4L60E value in a T56 tune (or reverse) will make the speedo do crazy things, or nothing at all

 

Thanks Pocket, this car had the tpi but when I went to 383 carb I removed all the computer harness including trans harness. Do you have a schematic of the gauge cluster or some way I can find that gray wire behind my instrument panel?

 

Pin listed is for the C207. Its a clear connector(engine side) and split black connector(dash side) near the old ECM. Cant imagine any reason that would be cut out

Its pin A (BRN or GRY) on the drivers side connector of the cluster for camaros

 

Thanks again thats what I needed to know, now maybe I can get this speedo working I will let you know after I get another chance to work on it.

 

Thanks Pocket now I have a working speedometer.

 

I just finished putting my 6.0 ls in my 92 camaro and i cant get the speedo to work.does anyone know what wires on the new pcm which is out of a 02 chev truck i hook up the purple and yellow wires to. I have them hooked up to the existing speed sensor wires that are on the 4l60e and my speedo just jumps around.

 

Why? the 4l60e is already connected to the new pcm right,that is how the ecm knows the speed you are going. All you need is the speedo output wire from the new ecm and wire it directly to the speedo gauge wire.As pocket mentioned above for the 90-92 camaros you are bypassing the buffer box.