After what seems like forever, I'm finally assembling my car for good. Well, for good for now. The car is a 91 camaro with a turbo 408 and t56. I followed the thread by pocket to build my harness and am running a 411 ecm. Getting my gauges to work has been a lot of work, my fault for miss matching body harness and under hood harness. . Ended up I was missing a couple of grounds for the cluster. Once I got that figured out I was reading every but the speedometer. Open hptuners and data log and the ecm was seeing speed. I tested the speedo out wire and did have continuity from the computer to the cluster, but when I probed with a test light , the computer wasn't sending a pulse to the cluster. I messed with the speedometer settings in hptuners and I got a reading on the gauge, but not the correct speed. Has anyone on here had this problem and does anyone know the proper setting I have to use for hptuners. . Any help is greatly appreciated

 

I've never programmed a stock PCM, but I think you can fine tune the speedo output by adjusting parameters in the software for gear ratio and such, right?

 

Yes you can. You can change for rear gear ratio, tire size, pulse per mile from the transmission, # of teeth on the output shaft of the transmission, and a few more things. I have the speedometer moving now by just throwing a random # in with hptuners but the speedo and cluster are totally out of wack.

 

i love dead threads where you need the info, searched google, was brought here only to find the OP never finished saying what he did, tried, or if he ever got it working..

sucks

 

What info are you still in search of? There is plenty of reference info in the stickies at the top of this forum and gages is one of them.