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Chassis Vs Battery Ground Differences?

dodge68charger

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My Aftermarket Electric Fan Harnesss and Led Tail Lights Call For Chassis Grounds

Any Issues With Me Running These To A Junction Post That Runs To The Negative Battery Terminal ?
 
My Aftermarket Electric Fan Harnesss and Led Tail Lights Call For Chassis Grounds

Any Issues With Me Running These To A Junction Post That Runs To The Negative Battery Terminal ?
No, but any other sensitive electronics on that same junction post might mind.
 
Something to be aware of.....
The original chassis ground straps were of a thickness/cross sectional area designed for THAT car's electrical loads.
Elec fans can draw 60 amps. Using existing chassis grds with high amperage fans might cause a voltage drop & the fans may not get the full 12v. So it would be a good idea to use a thicker grd cable, or leave the existing one in place & add a new one.
 
Any Issues With Me Running These To A Junction Post That Runs To The Negative Battery Terminal ?
Its an extra wire and a pointless one at that. A "body ground" is the nearest bolt to whatever you're grounding. The heavy ground to the block is to support the starter draw. The ground to the body doesn't need to be that heavy. Keep in mind that once the car is running all the juice is supplied by the alternator - not the battery. You want a heavy wire from the alternator to the + junction you're connecting everything to. The body ground only needs to be the same gauge as the main alternator wire.
 
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Also keep in mind that there are two amperage ratings for everything. A fan may draw 60 amps at startup (usually 40 or less) but only draw 5 amps when running. Likewise with all the other accessories. Chances are when all the lights are on and everything is running the total draw is around 50 or 60 amps. So you want alternator wiring and grounds that will handle that. And you want relays and fuses on all those accessories.
 
Also keep in mind that there are two amperage ratings for everything. A fan may draw 60 amps at startup (usually 40 or less) but only draw 5 amps when running. Likewise with all the other accessories. Chances are when all the lights are on and everything is running the total draw is around 50 or 60 amps. So you want alternator wiring and grounds that will handle that. And you want relays and fuses on all those accessories.
Yes, I agree with most of your valid comment, but during the times those items briefly draw their high currents, it "shocks" the system pun intended and other electronic items may not be happy with or able to handle those sudden voltage fluctuations that larger wires help to reduce.
 
The grounds on old cars were barely enough back in the day. Add in electric fans, EFI, electric fuel pumps, boom boxes, higher output alternators, a/c, computers etc the existing grounds are not going to cut it. Tie that in with rust, corrosion in lamp sockets etc and you'll end up with gremlins. The return path, ground, is major league important. Don't skimp here When I wire vehicles up, I increase sizes of the wires and add more than what they came with along with giving them the best connections possible. You can look at late model stuff and copy much of what the manufactures do. You would be amazed at the amount of grounds and locations on these rolling computers.
 
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