Giant ground wire from the battery to the engine block is justified. Giant ground wires anywhere else is electrical ************. Might make you feel good, but it doesn't accomplish anything useful.
The starter motor draws ~200 amperes when cranking. You need starter power and engine ground cables suitable for 200+ amperes.
There is nothing else on the vehicle that draws anywhere near that much current. Therefore, no need for Kryptonite ground cables.
I am upgrading all my charging and grounding wires on my 1995 Tahoe with 1/0 Knukonceptz Kolossus.
1/0 is insanely huge. 2 gauge would be plenty for the starter power and engine ground. 4 gauge for starter power and ground is common, and cheap-junk aftermarket cables are 6 gauge.
I would like some opinions as to if the set up and connections I have made are all proper and the best possible. For instance, I understand the more grounds the better, but 2 grounds going to the body? Is that right? Thanks for any help. Here's what I got:
Alternator positive to battery positive
Does GM route the alternator output directly to the battery? I'm guessing alternator output is routed to a power-distribution block that indirectly goes to the battery. The OEM routing makes more sense.
How many amperes does your alternator provide? I bet 6- or 8-gauge cable is plenty.
Alternator negative to engine block, located on fuel pump block off plate (Ground)
Is there an OEM ground wire at all on the alternator? Keep in mind that the alternator is at least partially-grounded via the metal brackets that hold it in place. I bet you could not use a ground wire at all, or a 10- or 12-gauge cable at most and be just fine.
Engine block to frame (Ground)
Battery negative to frame (Ground)
If the battery negative is directly connected to the engine block, and also connected to the frame, it really makes a frame-to-block connection redundant--but it's easy to pop a an 8-gauge cable in between frame and engine.
Firewall to frame (Ground)
Battery negative to firewall (Ground)
Again, if the frame is directly grounded to the battery, and the firewall is directly grounded to the battery, a cable from firewall to frame is redundant. If you insist, 8-gauge would be plenty.
Battery negative to fender (Ground)
I'd think that 8-gauge would be plenty. Maybe 10- or 12-gauge. How much electrical equipment grounds through the fender? How big is the OEM cable?
Battery negative to engine block. located on fuel pump block off plate (Ground)
That would be your largest ground cable, able to cope with the full starter current plus a little extra. 2-gauge is plenty. Same for the battery positive-to-starter solenoid cable--2-gauge is plenty, I bet OEM is 4-gauge.
The shop that overhauled my transmission has a policy of adding a ground cable from transmission to frame, looked to be 8- or 6-gauge. They even did a nice job of cleaning the rust off the frame where they made the connection.
Make sure all your connections on both ends of the cable are to bare, clean metal--no rust on the frame at the contact point, for example; and no corrosion on the copper cable ends. The ground wires are often connected with star washers. The edges of the star washers dig through surface corrosion for a low-resistance connection. You might want to consider buying some appropriate-size star washers to go with your new cables.
Adding some corrosion protection to the cable ends once attached to whatever they're connected to makes some sense. any one of the many kinds of Glyptal paint is commonly used, as is NYK 77 grease. The grease works OK, but if you brush up against it, you're going to wipe it off the connection and onto your clothing.
http://glyptal.com/
https://www.amazon.com/Truck-Lite-97944-Corrosion-Preventive-Electrical/dp/B002HC396G