Been a while since I was on here so Hi to everyone
Recent swap to carb 350 from 87 Suburban, replacing 305HO in my wifes 84 Z28 automatic. Current ECM is CJW 1226455 with matching chip for the 305 auto. I need to know if I can (or need to) replace the chip with an 84 350 carb chip from BDS 1226455 ECM (auto) or replace the whole ECM with the BDS (or other) 1226455 ECM (auto) module?
I realize there are numerous posts regarding swaps here and I have searched them for this particular info but cannot find this specific issue. If someone can help me with this I would appreciate it
thanks
Bruce
Recent swap to carb 350 from 87 Suburban, replacing 305HO in my wifes 84 Z28 automatic. Current ECM is CJW 1226455 with matching chip for the 305 auto. I need to know if I can (or need to) replace the chip with an 84 350 carb chip from BDS 1226455 ECM (auto) or replace the whole ECM with the BDS (or other) 1226455 ECM (auto) module?
I realize there are numerous posts regarding swaps here and I have searched them for this particular info but cannot find this specific issue. If someone can help me with this I would appreciate it
thanks
Bruce
five7kid
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May 4, 2026
Stick with the 305 HO chip & ECM.