Ammeter bypass
My thought was that the reading at the battery would be higher with the charging circuit no longer going through the bulkhead.
..and would also be higher than the reading taken by a meter supplied from the dash.
Here's how the voltage drop problem works. It is "key" with the voltage regulator IGN terminal which is where the VR reads voltage as well as gets power for the VR and field. The collective drop through the harness terminals and connections DROPS the voltage from the battery down to the VR. So the VR is seeing a reduced voltage. BUT the VR is designed to provide a setpoint AT THAT TERMINAL. So the VR ramps up the alternator until the VR IGN terminal is 14V AKA whatever the setpoint is. Now the voltage at the battery goes high because of the drop in the harness. The charging voltage the battery sees is the difference between the harness drop and the VR setpoint. If you have 1 volt drop in the harness, then you have 14 +1 at the battery.
Now you have UPGRADED the voltage drop and eliminated it, so the battery voltage and VR setpoint BECOME CLOSER. If you have "zero" drop in the harness, then the VR IGN terminal and the battery will be exactly the same voltage
Don't forget ground..........if there's a drop between the neg battery terminal and the VR mounting flange THAT drop will add to the battery voltage.
ALSO REALIZE that just adding a big jumper between the alternator and the battery DOES NOT ELIMINATE all the drop.
You can still have ground side drop..........
and with an original harness, and if the only change is a jumper from alternator to battery, you still have the "drop path".........
Starter relay..........fuse link........bulkhead connector.........ammeter..........ignition switch connector.........through the switch......back through the ign switch connector,........back out the bulkhead on the "run" line.
