Been wanting to do the big three for a while. I just have a few questions on the topic. Firstly, I've found the 1/0 Gauge welding wire at a local shop. Gonna use that and use red heatshrink on the end of the positive wire, black on the negative for lack of confusion. I know the big three is as follows Alternator Positive to Battery Positive. Battery to Chassis Ground. Engine to Chassis Ground. But, while I was out surveying my engine bay, I find that my negative battery cable goes to the engine. Not the chassis. Well, there is a 16-18g wire that goes to the fender, which is really freaking pathetic, but I digress. Negative Battery Cable: Crappy sixteen gauge wire to Chassis: Where the bulk of the negative cable runs to: When I run the new wire, should I run a thick wire over to the engine like it is now? Or should I just ground it to the chassis and then ground the engine to the chassis really well? I think it'd get a bit cramped if I tried to run a 1/0 to chassis and then another 1/0 or even down to a four over to where the ground currently is. Then I come to look at the positive wire. Jeeze. Did GM cluster**** that or what? It has a large gauge coming out of it (for the starter) and a a 8 gauge I'd guess going to The Rubber Nemesis. What the hell is this thing? It's got an 8 gauge going in, and 8 gauge going out, and two 16 gauge (one orange one black) going in or out. The 8 gauge goes out to the alternator post. The orange 16 goes to a weatherpack connector in the harness nearby. The black 16 goes up to a fuse holder, which then has an orange that comes off of it, which goes into a weatherpack into the harness. Positive cable: The Rubber Nemisis: The Orange Weatherpack: The Fuse Holder: The Orange Weatherpack Numero El Dos: Now, I've been wondering for a while how I'm gonna get rid of that thing. I don't know if the wires are connected, or what. Some people say it's a fusible link. Doesn't look like any fusible link I've ever seen! And it's connected to the alternator! Is it a primitive distribution block? Does anyone recommend a way to replace this thing? Ugh. It's a mess! Also, the factory battery cable ends are rubber coated. I like the cleanliness of the look. Are there any aftermarket battery cable ends that look similar? And, on a related note, the positive terminal needs a fat wire to the alternator, AND a fat wire to the starter. Has anyone conquered running two large wires right there? Any pics? Advice? Thanks for any help!

Anyone with any ideas on this? My wiring schematic shows the thick wires for the alternator and the black wire tapping onto a single point there, and the orange wire as an intermediate wire that turns into a fusible link (red wire) for the fans.

Does the fan wire and fuse wire just tie into the alternator wire here so they get constant 13.4v without tying onto the battery?

have you measured your "rubber nemisis" im not sure but i would suspect that it was a noise "high frequency" filter due to the fact that it is attached to an electric motor and an alternator. if you measure across it and it appears to be a short them its probably just an inductor "noise filter" alot of times they are not needed in my opinion but in this case im not sure.

This is the schematic I'm looking at.


And the large red thing says "fusible link" and I know that's the wire just before the second connector.

I though it was just used to tie in the orange wire for the ECM to the alternators wire?

Apparently it's the MAF Power Relay, MAF Burnoff Relay, Fuel Pump Switch, Fuel Pump Relay, ECM, and both fan relays. That's a pretty important little connector there. I think I'm just gonna buy a distribution block that has two 1/0 gauge connectors and three 8 gauge. Figure something out. Oh, and throw a glass half amp fuse between the block and those relays.

Looking at that more the connectors different than mine. I guess since Im carbed, It looks really similar though, Im surprised noone who did this mod chimmed in already, tons of people on here have done it. Be sure to post pics up when you do it because im kinda nervous about doing it but I really want to.

Did you end up doing this?

Not yet. More pressing matters!

Like, I need carpet! Still on my to do list though.

I'm not sure about all this "big three" and "nemesis" type of talk; never heard of such. I'm just going to leave all of that aside.

However, many years spent in electrical engineering of various sorts, has taught me the wisdom of putting the copper where the current goes; and of making that path as short as possible.

In the case of a car, the SINGLE BIGGEST current flow that occurs, is operating the starter. The starter current is AT LEAST twice as much as the maximum possible flow of the ENTIRE rest of the car, operating simultaneously; i.e. if you operated both power windows, all 3 power seat motors, AC with blower on high, headlights on bright, rear window defogger, wipers on high, and so forth, ALL AT ONCE, it's still only a fraction of the starter draw. That means, the SINGLE BIGGEST and SHORTEST wiring path, should be the one that carries the starter current; from the + batt term, to the starter, and then when it comes back out the ground side of the starter, back to the - batt term.

Since the starter body is connected ("grounded", as people say, although that word is a misnomer) to the engine block, and that connection is FAR "bigger" than a wire, then the - batt cable should conect to the engine block, or as close to it as possible.

Meaning, the way the factory did it, is correct; although it could be improved slightly maybe by putting the - batt cable under a blot that goes straight into the block. But that's VERY minor.

I would NOT, UNDER ANY CIRCUMSTANCES, connect the batt to the chassis, and then the motor to the chassis; as this would force the starter current to flow via that extra-long path. Not in accordance with good design principles.

If you feel for some reason that the factory's connection of the chassis to the battery is inadequate, leave the - cable hooked to the block like it is; but add a BIG HEAVY cable from the block to an electrically solid point on the chassis. I'd suggest connecting from a bell housing bolt to a big heavy piece of hardware that's NOT a sheet metal screw, on the firewall; something like, drill a 3/8" hole, and use a 3/8" brass or stainless bolt and nut through the firewall to clamp it with a stainless star washer between the cable "eye" and the chassis metal, after sanding the metal bare and putting some dielectric grease on it to keep it from rusting.

"Ground" is too often used much like "timing" or "EGR" or "external balance" as the cause of problems. While each of those things is a valid concept with a well-defined meaning, and each must work properly for the car to be its best, they're "mystical" "mysteries of the universe" usually used by people to "explain" happenngs that they can't otherwise figure out, usually because they have some sort of notion in their mind about how stuff works that isn't how it really works, and rather than learn how something works, they just want something nebulous and fuzzy to "blame". Not a real good way to go through life.

This is an old thread, but I read up on this some more and someone who did this on there car just left the orignal alternator wire to avoid messing with the weird black thing and just added the new wire in there along with the original and fused the new wire.

I'm curious to know how it panned out. I wanted to do the Big 3 too and came across the "rubber nemesis" and decided to try other things first too. On my 92 Z, the battery is grounded to the block through a bolt directly, not to a bracket...

Any update?

Not really. Haven't made any progress. Been working on other things. :/