NBS cluster with LS swap?

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slow_c1500

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Anyone ever kept the EVAP on an LS swap, and might be able to answer my question for what wires to keep?
 

Leeztruk

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Lemme get this straight. You're in California, you wanna do an LS swap in an older truck, and you're concerned about emissions standards for your state, yes? Have you considered seeing a CARB referee for what is actually needed to make your swap legal for your state? I know there are folks who have pulled this off, but they had to jump through hoops to get it done. You want to get your evap system up to more modern functionality, but is your fuel tank able to meet those demands (pressure sealing, for evap monitoring and evacuation, etc.). The tank will need to have a pressure sensor installed. If you need to have the evap recirc. solenoid function, then that wiring from the stock LS harness should be in place, not removed as the aftermarket harnesses have done. Also, most aftermarket harnesses only have wiring for the front O2 sensors. You're gonna need front AND rear sensors. Getting your instruments in your cluster to work is pretty straight forward. You just use the wiring from those senders and attach them to the LS oil pressure/temp senders. Not sure on the speedometer as you have a seperate DRAC for the speedometer. Don't know if the newer PCM will feed the DRAC directly or if it will go directly to the speedometer.

Speaking of PCM's, when you get yours reflashed, make sure you tell the reprogrammer that you NEED the emissions functions left intact to meet California inspection requirements, and to just take out VATS so your engine will start. Have you researched info for doing engine swaps in California? That may give you a more direct knowledge for your swap. Good luck.
 

AK49BWL

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Lemme get this straight. You're in California, you wanna do an LS swap in an older truck, and you're concerned about emissions standards for your state, yes? Have you considered seeing a CARB referee for what is actually needed to make your swap legal for your state? I know there are folks who have pulled this off, but they had to jump through hoops to get it done. You want to get your evap system up to more modern functionality, but is your fuel tank able to meet those demands (pressure sealing, for evap monitoring and evacuation, etc.). The tank will need to have a pressure sensor installed. If you need to have the evap recirc. solenoid function, then that wiring from the stock LS harness should be in place, not removed as the aftermarket harnesses have done. Also, most aftermarket harnesses only have wiring for the front O2 sensors. You're gonna need front AND rear sensors. Getting your instruments in your cluster to work is pretty straight forward. You just use the wiring from those senders and attach them to the LS oil pressure/temp senders. Not sure on the speedometer as you have a seperate DRAC for the speedometer. Don't know if the newer PCM will feed the DRAC directly or if it will go directly to the speedometer.

Speaking of PCM's, when you get yours reflashed, make sure you tell the reprogrammer that you NEED the emissions functions left intact to meet California inspection requirements, and to just take out VATS so your engine will start. Have you researched info for doing engine swaps in California? That may give you a more direct knowledge for your swap. Good luck.
96 doesn't have an external DRAC unless diesel or V6, speedo is fed by the PCM in trucks with the 5.0, 5.7, and 7.4 engines.
 

slow_c1500

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I may be relocating states later on, or if I stay in CA I will just register it in South Dakota, since it's legal to have your car registered there and not be an SD resident. I am less concerned about meeting the retarded smog requirements, I simply want the EVAP system to work as it does on the OBS. In this case, do I only need the purge solenoid (this is the only EVAP-related connection that my harness and the LS harness have in common), and then run a custom hose from OBS canister to LS solenoid?
 
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