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To all that are following this thread, as the OP I would like to invite any other electrical knowledge anyone is willing to post here, in the hopes this thread will become a great resource(it already has WAY surpassed my expectations!!!) for all of us, especially now in the age where we are getting into more and more sensitive electrical issues and systems.
One thing that comes to mind would be charts like used to figure wire gauge for load and length, etc. Math used in electrical work is another.
At this time I would also like to thank all that posted here with info. I appreciate it, and have learned a lot so far. Thanks, Greg

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Radiator electrolysis can be a real killer of aluminum radiators. To test, VOM on 2 vlt scale. Negative probe to a known good grd. Positive probe in the coolant ( make sure it does not touch rad neck, etc). Take a reading. Take another reading while starter is engaged. Start the car and turn all electrical circuits on. A reading of .2 volts or above = bad ground. A change in voltage as you turn circuits on and off is a good way to isolate the problem. This is referred to as type "A" electrolysis. If the voltage does not vary as you turn stuff on and off, but remains above .2 vlts, that is referred to as type "B" electrolysis. This indicates acidic fluid. Dump the coolant, flush the system, and replace the coolant. OR, a quick check = stick your finger in the coolant. If it comes out black, you have an electrolysis problem. Obviously bad news for heads, block, or anything else aluminum. A "known good ground" would be the - battery post.

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As I said when more information was available I would post it. Some understand the next paragraph. So for those who don't. When current is flowing through a wire there are magnetic lines of force that encircle the wire. The closer another wire is to the current carrying conductor the more the likely hood that those magnetic lines of force will induce current in the 2nd wire. We also can have voltage "leakage" where the insulator isn't sufficient and voltage can jump to the next wire. The last item that has been talked about is "flyback". An example of flyback would be when the circuit for the primary winding in the coil is opened its magnetic field collapses. This induces voltage in the secondary winding firing the plug. When this energy dissipates through the secondary winding it induces voltage back into the primary winding. This voltage is known as flyback. After talking to 6 electrical engineers I was directed by all of them to go and talk to the same person. This is what I learned from our EE PHD. As we've talked about having all the grounds in close proximity is a good idea. He was right on board with Monty's copper bar. He also liked the separate ground cable, but for a different reason. Running both a separate ground cable and the positive lead side by side helps cancel noise. That could be the same reason running the box leads to the battery was beneficial (leads side by side). His definition of what he thought would be the very best wiring.
#1 both hot and ground cables side by side.
#2 the hot cable directly to the starter, with feeds to a remote power stud and the alternator.
#3 the ground to the copper ground block.
#4 the block and heads grounded there.
#5 clean properly sized terminals and cable.
#6 twisted pair to sensors. with optional shielding grounded at one end
#7 care in running any sensor wiring near plug wires and or power cables.
Also note: shielding helps with voltage noise but doesn't do much for magnetic force.
In closing obviously in the majority of cases we get away with less. Make the choice of what you think you need for your application. I would think after reading this thread you can make an informed decision.
Doug

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As I said when more information was available I would post it. Some understand the next paragraph. So for those who don't. When current is flowing through a wire there are magnetic lines of force that encircle the wire. The closer another wire is to the current carrying conductor the more the likely hood that those magnetic lines of force will induce current in the 2nd wire. We also can have voltage "leakage" where the insulator isn't sufficient and voltage can jump to the next wire. The last item that has been talked about is "flyback". An example of flyback would be when the circuit for the primary winding in the coil is opened its magnetic field collapses. This induces voltage in the secondary winding firing the plug. When this energy dissipates through the secondary winding it induces voltage back into the primary winding. This voltage is known as flyback. After talking to 6 electrical engineers I was directed by all of them to go and talk to the same person. This is what I learned from our EE PHD. As we've talked about having all the grounds in close proximity is a good idea. He was right on board with Monty's copper bar. He also liked the separate ground cable, but for a different reason. Running both a separate ground cable and the positive lead side by side helps cancel noise. That could be the same reason running the box leads to the battery was beneficial (leads side by side). His definition of what he thought would be the very best wiring.
#1 both hot and ground cables side by side.
#2 the hot cable directly to the starter, with feeds to a remote power stud and the alternator.
#3 the ground to the copper ground block.
#4 the block and heads grounded there.
#5 clean properly sized terminals and cable.
#6 twisted pair to sensors. with optional shielding grounded at one end
#7 care in running any sensor wiring near plug wires and or power cables.
Also note: shielding helps with voltage noise but doesn't do much for magnetic force.
In closing obviously in the majority of cases we get away with less. Make the choice of what you think you need for your application. I would think after reading this thread you can make an informed decision.
Doug

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Sounds like your engineer would wire something the same as I do, with the exception that I prefer to run a Ford starter relay, in lieu of running hot wire directly to starter. Good info, glad to know I appear to be doing something right.......LOL!!

And I agree that "twisted pairs" are a good idea and I do it often with things that can backfeed, like trans brake solenoids, buttons, coil wires, hots and grounds of any electronics, etc. Guys often ask me, "how do you do that".........it's pretty simple really. The pair you want "twisted", simply put the ends of the wire in your cordless drill, tighten the chuck and twist away. Be careful, because you CAN break it if you twist them too tight.

And I know it is EASIER to say ground your trans brake or electric shift solenoid, right AT the trans or shifter.....BUT, these two items are notoriously bad for feedback when the circuit collapses. Also remember that these inputs likely run through delay boxes, shift modules, or ign boxes. Feedback can create havoc with all these devices, making consistent release and operation sketchy. So take the time, run a full length twisted pair, ground them clean and you may solve some issues.

Monte

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Is it bad practice to have a few different items on your car ground to the same location, for example, lights fan and ignition on the same lug.

Good or bad.

I am tracking an issue that's why I ask

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So anyways, why wouldn't having a separate power and ground buss for the race car stuff not work? So far that MSD seems to be happy the way it is.

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Like this in the picture, except not grounded to the chassis... The rest of the stuff like fans, water pump, fuel pumps, lumped in with the car stuff like lights. BTW, this is kinda how the car is wired now and the box sticking into the space a passenger's legs would normally go is a hassle.

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Hi Doug,
I am chasing an ignition issue. I rewired the entire car this last summer. I chose to use a 20 circuit universal harness, way more circuits than I will ever need but I did it for a reason. Since the rewire I will be driving down the street and for no reason the car just stops(Lights Out no power) it has done this just sitting in the garage running. I will cycle the power switch the care restarts and everything is fine until it happens again. its really odd but I can only think its a ground or excess of grounds together or it is in my msd box.

what are your thoughts

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I would check the master shut off... to lose total
power your doing 2 things.. you killed the alt and
the battery.. the master controls both of them..
next time it does it put your multi meter across
the master and see if its open

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Hi Doug,
I am chasing an ignition issue. I rewired the entire car this last summer. I chose to use a 20 circuit universal harness, way more circuits than I will ever need but I did it for a reason. Since the rewire I will be driving down the street and for no reason the car just stops(Lights Out no power) it has done this just sitting in the garage running. I will cycle the power switch the care restarts and everything is fine until it happens again. its really odd but I can only think its a ground or excess of grounds together or it is in my msd box.

what are your thoughts

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Hi Doug,
I am chasing an ignition issue. I rewired the entire car this last summer. I chose to use a 20 circuit universal harness, way more circuits than I will ever need but I did it for a reason. Since the rewire I will be driving down the street and for no reason the car just stops(Lights Out no power) it has done this just sitting in the garage running. I will cycle the power switch the care restarts and everything is fine until it happens again. its really odd but I can only think its a ground or excess of grounds together or it is in my msd box.

what are your thoughts

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When you say lights out do you mean more than just the engine?
Doug

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yes Lights out means all power the car sputters to a stop all lights, fans, fuel pump etc. go out. I probly should replace my Shut off switch. I am also going to separate all my grounds as was mentioned above. Lights with Light, Fuel by its self, fan by its self and ignition by itself. I have all winter to figure this out. but already cant wait to drive it ion the spring

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yes Lights out means all power the car sputters to a stop all lights, fans, fuel pump etc. go out. I probly should replace my Shut off switch. I am also going to separate all my grounds as was mentioned above. Lights with Light, Fuel by its self, fan by its self and ignition by itself. I have all winter to figure this out. but already cant wait to drive it ion the spring

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