CurtisL

Thanks Adam, I was curious about tying the signal grounds together, but I also didn't want to create ground loop issues or anything. The factory ecu and the link will be grounded to the same location, so I wasn't sure if that was good enough.

I'm currently wiring up my Crank and Cam trigger signals on an LS6 (similar to LS1) in a piggyback configuration with the factory ecu and had a quick question. I'm planning to run a trigger signal wire and signal ground wire in a shielded cable to the Link ECU. I plan to allow the factory ecu to supply the +12V supply power as is done in the factory application, and then splicing the factory signal wire to the signal wire going to the Link ECU. Currently it appears that the factory ecu has a pullup resistor according to the factory schematics. Would this work appropriately as long as the pullup in the Link ECU was disabled so that there are not two pullup resistors on the same signal wire?

When piggybacking and turning off the pull-up resistor, does that affect the calibration of the sensor? I would imagine you need to know what the OEM pullup resistor is to then recalibrate correctly, right? I only ask as I have just jumped into this looking to see if I can piggyback a few sensors on my GM ECM so my factory cluster will work correctly.