I just installed a "Glow Shift Elite" Tach in my 80 F-150, for some reason it is telling me that the RPM's are double what they really are. I have hooked everything up to the right wires, I have set it to V8, I am stumped, any help?
Are you sure you have it set to 8? It sounds like you have it set to 4. There's not anything else that could cause the problem unless it's just a faulty tach.
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