The part number for the Classic EFI (gray box) is a honda # 36531-PO7-OO3. Another part number is a Bosch # 13246. Those are the same unit reboxed.
There is a newer one available the part number is NGK 24300.
Any of these need a calibration value loaded into them. You will need to call Fast and give them the box number and they can tell you what you need to do.
The sensor cost $249.99 from Ballenger Motorsports you can contact them for more information.
I hope this helps. You can e mail me at
pmur182@aol.com.
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