I performed a sbc V8 swap about 12 years ago. When I did the conversion, I used the existing harness and have my 1 wire alternator running through the Amp gauge on dash. Did not do any other re-wiring. Recently, I added the Holley Sniper EFI and Hyperspark Ignition (major improvement). I have also added a Stereo and a couple of other gauges and have added another fuse block in the engine bay that is tapped off one of my fuses so to have additional ignition switched sources for other accessories. I am now noticing that I am losing voltage to my battery. My alternator is putting out 14.32 v but the battery does not see this (more than a volt drop). I have also read that it is not advisable to run additional currant (amperage) through the dashboard amp gauge (have read can cause wires to burn and even start a fire?).
I tried to just disconnect the alternator wire to existing harness and running it straight to the battery but when I did this it caused the relay in my high-pressure full pump to kick on (even though the existing wire from alternator to harness was disconnected, makes no since).
I am thinking that since the alternator is running through the dash amp gauge, and through the ignition and fuse block through undersized existing wires is why I am losing voltage to the battery.
So, looking for some help from anyone who may have experience in the wiring of these FJs or has done a V8 conversion and may be able to assist on what I should do. I have attached 2 diagrams below, one showing what I have verified is running through my fuse block (and what I have tapped into for other accessories) and a 2nd showing the FJ40 wiring harness with the wires identified that I need to modify. Also note that the wiring diagram shows many sources (such as head lights) originally running off the separate alternator regulator that I no longer have since the 1 wire alternator has regulator built in, so all power is running through harness and fuse block.
I tried to just disconnect the alternator wire to existing harness and running it straight to the battery but when I did this it caused the relay in my high-pressure full pump to kick on (even though the existing wire from alternator to harness was disconnected, makes no since).
I am thinking that since the alternator is running through the dash amp gauge, and through the ignition and fuse block through undersized existing wires is why I am losing voltage to the battery.
So, looking for some help from anyone who may have experience in the wiring of these FJs or has done a V8 conversion and may be able to assist on what I should do. I have attached 2 diagrams below, one showing what I have verified is running through my fuse block (and what I have tapped into for other accessories) and a 2nd showing the FJ40 wiring harness with the wires identified that I need to modify. Also note that the wiring diagram shows many sources (such as head lights) originally running off the separate alternator regulator that I no longer have since the 1 wire alternator has regulator built in, so all power is running through harness and fuse block.
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