For you LS3 conversion folks..
#1
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Have a question as I stumbled across something last night. My LS6 intake had a vacuum port at the back of the manifold where I would attach a small vacuum line that runs into the main harness area, however the LS3 does not have this provision. Actually, it looks like it is in fact molded with a vacuum port and it is capped/plugged and I really don't want to break the port off altogether trying to open it if it isn't supposed to be. Any ideas??
#7
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IIRC that is for the heater core A/C. When I ditched the core in the firewall I had to pull that back off the rear of the LS3 manifold and vacuum cap it. The line is bundled into the harness right next to the PCM.