I put a 96 LT1 into my 91 RS. I want to use my existing cruise setup to work with the new motor. All I need is a 2k pulse per mile feed into the cruise control module. Well, the 96 vss is a 4k/mile pulse. The old vss sent its hi and lo signal into a vss buffer which then sent it to various places, including the cruise control module. The new vss sends its info to the pcm and the pcm sends out its signal to the cruise control module. Well, like I said earlier, my old module needs a 2k/mile.

How can I split the signal in half?

Thanks, Mike

 

You need a DRAC. You should have one from your 91. There should have been one of these Digital buffers called a DRAC screwed onto the side of your 91 ECM. Its a small white plastic box. Run your VSS out signal from C220 pin "G" Drk green with white stripe on it, into this DRAC and run one of the split output wires to your cruise VSS input wire. sorry but I dont have a 91 service manual so I dont know what wire it is on yours.

kingslam
ps I do have an extra drac laying around someplace in my shop.

 

I am not sure I follow you. Looking at the 91 service manual, the buffer has only two inputs. One for the vss lo, and one for the vss hi which both come from the vss. Are you saying to run it to either one of those inputs?

Then you said run one of the split output wires to the vss cruise input. One of the output wires from the buffer?

Sorry about the lack of knowledge. I am trying though

 

DOAH yup thats right the 91 uses the hi/lo inputs to the drac, so you should be able to tap a hi and lo output wire to your VSS wires going to the PCM, and then run them to your DRAC. then use one of the 2000 ppm signal wires which should already be there going to your cruise module. what did you use for your speedometer??? it should have the same signal as your cruise?

kingslam

 

I tried that when I was working on the harness and my speedo was going nuts. I used the original wiring to the vss and spliced into the new wiring to the pcm thinking that would take care of the speedo and cruise but as I would drive the speed would go all over the place and in no was related to how fast I was going.

Are the vsss the same or do they generate a different signal? If you think it should work I will try it again but I think I wired right the first time.

Also, my speedometer uses the 4k pulse/mile signal from the drac. Everything else use the 2k.

What now??

 

How about putting this is the lines to the speedo:

DAKOTA DIGITAL SPEEDO INTERFACE

 

i have a dakota digital interface that i have for sale. it would not work with my paticular application, but is in excellent condition with instructions, garrented for $45. grape@adelphia.net

 

Sure, what you want to do can be done-without running around in circles. Best to call to find out what you need. 512-828-0227

jim