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big block battery ground locations?

vegiguy

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Where was the battery ground ("-") cable originally grounded to the engine and body on early 70's cars?
 
I'm not 100% sure on this, but I believe the negative battery cable grounded to the core support near the battery. The block was grounded to the firewall from the passenger side head.
 
I'm not 100% sure on this, but I believe the negative battery cable grounded to the core support near the battery. The block was grounded to the firewall from the passenger side head.
So you don't think the engine was grounded directly from the battery? When you go to buy a negative battery cable for a '73 Road Runner with a 400 all the parts stores sell you a 32" long battery cable, which is pretty long for a negative battery cable. All the wiring diagram in the shop manual shows is a 4 gauge and a 10 gauge wire going to ground from the negative battery terminal. I sure wish you could get assembly manuals for our cars like you can for GM cars because this sort of thing is shown very clearly in them.
 
Here's a non AC RR that has the Negative cable grounded to the throttle return bracket bolt on the intake:
rr-id-004.jpg
[/URL][/IMG] and here's an AC car that has the negative cable grounded to the AC compressor:
Imagen_002.jpg
[/URL][/IMG] . Don't know if this is right but it's what I found in my Mopar picture file.
 
Don't know why those images didn't show up. I took the IMG URL from my Photobucket using the above toolbar. Let me try it a different way:
Without AC:
rr-id-004.jpg


With AC:
.
Imagen_002.jpg
 
You're right. I forgot about that one.:BangHead: haha
I'm sure somebody will respond that will have a more definitive answer for you.
 
Pretty much depends on added stuff on the engine...just like bolted onto the AC compressor...still directly grounded to the engine.

Takes two grounds...one from battery to engine...one from engine to firewall (body/frame). If you look at the heads, there's an extra bolt hole on the intake face, one up front (battery side), one rear (passenger side), where the grounds are usually mounted. But, sometimes they get blocked by added equipment.
 
I thought the battery to engine ground would go to one of the extra holes on the left front of the engine, but then I realized that that would end up being right under the power steering pump when the pump was installed so that shot that idea. I'm thinking the ground to the left front corner intake manifold bolt is correct, at least for non-AC cars (maybe even for AC cars, too). I'm ambivalent about whether the AC cars would have been grounded to the AC compressor - they could have been. Even GM cars often had the battery grounded to a bracket on the engine and not to the engine itself, so cars being originally grounded to something on the engine and not the engine itself is not unheard of.
 
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