big 3 upgrade on integra, fuse box?

Hi, I had my HO alt and 0 gauge wiring done professionally and for some reason he claimed that he couldn't fit the stock wire so he took it out. The problem begins with the fact that the Integra wiring goes from alternator->fuse box->batt. positive. So what he did was wire the 0 gauge to the fuse box, and then left a stock wire going from the fuse box to the battery (which defeats the purpose of using 0 gauge). The way the fuse box is I'd have to tear it apart to fit another 0 gauge wire so that's not an option. Here is a picture of what I'm talking about: I need to get 0 gauge all the way to the battery, and the fuse box kind of prevents me from doing this. Is it possible to just run straight from the alt. to the battery and then add a wire battery->fusebox, or must the alt. wire pass through this?

That does not look professionally done to me. I dont see an upgraded ground wire from the (-) battery post. I dont really understand what is all under the hood of your car, so im sorry I cant help. Heres some info about the Big 3. https://www.the12volt.com/installbay/forum_posts.asp~TID~73496~PN~1

Well theres a reason for the ground, that was something Im doing myself. He was just doing the HO install and alternator wiring. I understand how the big 3 works, but most cars just go straight from alternator to the battery and dont have this fuse box ran in the middle.. And because he didn't leave the stock wiring in, I have to find a way to get 0 gauge all the way to the battery while getting this fuse box power.

As far as I am concerned, there is no need for an alternator to battery fuse, EXCEPT to protect the cable in case it rubs bare or comes loose (from the alternator end). Older cars never had them. I suspect they figured the same safety/security as the starter-motor cable. (No fuse; make it heavy enough and physically protected enough etc.) I sarcastically wondered is fuses were introduced in a vain attempt to prevent Bosch alternators from blowing. Others may have introduced it to protect their alternator's power diodes in cases of reversed battery connections. (Yet my mate's 1966 23A alternator survived SEVERAL reverse hits from his fully charged and brand new incorrectly(!!) labeled battery terminals!) My experience has been that reverse connections blow alternators with fuses, and does not blow alternators that do no have fuses. As to protecting the cable or alternator from battery end shorts, alternators are supposed to be self limiting - their windings are normally designed for the magnetic saturation etc, and their diodes should be likewise rated. But this morning I read of burning alternators due to bad batteries. Maybe a non-OEM alternator rewound for certain performance? Certainly HO alternators seem to have poor output at low RPM - I assume thicker but less windings for higher current capability. But what then of magnetic saturation etc? Or are all your alternators that bad? Anyhow, my experience is that fuses do NOT protect alternators.    Hence I reckon you can skip the alternator to battery fuse. And why have a fuse to the fusebox from the battery or alternator?    And why involve the fusebox anyhow? Surely you have specific distribution to you higher power loads? But remember too that a fat wire with a short thin bit is still much better. It's not the same as a restrictive water pipe that DOES choke water flow. The "extra loss" is merely its higher resistance (per length) times its short length. The bigger risk is fusing, but if short enough, it shouldn't fuse because the thicker 0G conduct its heat away quickly. (Remember, cable current ratings are based on a "free length" of cable...) Likewise the 0G will keep the short smaller gauge cooler compared to a longer piece, hence lower resistance.... But as usual, decide what your target is. Usually it's big amps in the back rather than the battery. Normally the battery only requires enough cable to carry 2 Amps - it's only for cranking that the cable is upscaled, and to a lesser extent the discharge-replacing current (which usually isn't more than a few tens of Amps for long anyhow.) But then you have the thumpers - whatever it is that draws peak current. And if the alternator can't supply that, you are looking at (say) a 1.5V drop or more as the battery takes over.... Plus whatever IR drops along the distribution path from whatever power sources exist. But yeah - that is a strange "professional" job.   To go to the trouble of dropping resistance, only to add a resistance (the fuse) and more resistance (the longer loop of cable). And to actually create an insulation-chaffing in the process! Professional used to mean quality. These days it has been relegated to its literal "paid" meaning. But I still prefer to crap my own pants for free. It might be just as warm, but it's cheaper and IMO doesn't stink as bad.

oldspark wrote: But I still prefer to crap my own pants for free. It might be just as warm, but it's cheaper and IMO doesn't stink as bad.

LOL. Funny, but true.

For Pete's sake Godd Dan It, I wish you'd stop brown nosing! You know as well as I do that my crap smells far worse than yours. And I'll admit, you may have a better class of sht than I. Bottoms up. Peter. PS - Any puns accidental or otherwise are intended, even if they leave a bad taste in your mouth.... or any other post-recipient. PPS - oooh those puns! Now what was the OP's question?

Well although that's an interesting side of the discussion I bought the fuse because a lot of places seem to think it's extremely dangerous to not use one, and right or wrong I think I'd rather not take the chance -- it's not like fuses are expensive. About the loop, there really isn't much room under my hood, especially for something that big so I couldn't really think of a better way to actually mount it so that the hood has clearance to close but that was his doing. Oh, and the stock wiring in this car actually went alternator->fuse->fusebox->batt. positive -- which is probably not the best setup but now I have to deal with it.

nstillmatic wrote: ...a lot of places seem to think it's extremely dangerous to not use one

They weren't per chance the same people that told kenwood_nut (for his 120V AC switch issue) "there MUST be a ground to the switch, and if there isn't, to make one"?     (NOT to be confused with the couple that also told kenwood_nut "that there shouldn't be a ground to the switch"!) Regulations aside, it seems yet again that the minority were correct. And do those people really think, or just seem to think? I'd rather a place that knows! But from a survey some years back, it seems very few do know. And usually not those that were adamant that they did know! But the test is in the asking - "why the fuse?" - then you'll see.... Eg - if to protect the cable, fuse at the battery and, or alternator end, or both? Or why isn't it dangerous for the starter-motor to have unfused +12V at its heavy terminal? (And that's probably further from the battery with a less flexible cable!) (XJ6 owners - quiet please!! HowieQuips however will be tolerated.)    And I do find it amusing when supposed safety features cause a hazard, like (I suspect) your length of unfused 0G to the left and above the 200A fuse. (Honestly, why is that fuse SO FAR from the battery? If it were mine, I would remove it and run a shorter and physically secure cable. It is currently a short waiting to happen! Else a short waiting to become current.)    Incidentally, alternator to loads and then to battery was the preferred wiring. It was often done in pre-HID days for headlights. And it should be common for hi-power audio setups - except perhaps where power ripple is a problem (noisy rectifiers; no other battery or cap closer to the amp else HU etc). Those that use the "absolute ground" argument(s) should agree that alternator to loads makes more sense anyhow, except for those with bigger systems where the biggest concern is when the battery is the absolute ground. The point being that the correct topology depends on your requirements and situation. (IE - alternator to load, or to battery. BIG audio systems usually take the alternator to the REAR or remote battery, and feed the main/front battery from the remote/rear battery.) Apologies for repeating yet again.

Without stirring the crap, a) Fuse is much too far from the source, should be 4" (10cm) from its source. b) 200amps. If you pull enough juice to blow that your engine block will melt. As an example, on the above vehicle the main ignition fuse (in that fusebox above) is rated at (only) 50amps. Throw away the fuse and go directly to the battery. Incidentally we all have a wrong impression here, I don't think it goes "through" the fuse box, I think they are joined but then I think may-be it was beyond the poster's capabilities to remove the cover.

Okay, I made a few changes before I saw your last couple posts. This is what I have right now: Alternator->200a fuse->batt. positive->fuse box The fuse box is being powered and everything seems to work. So there is no reason to have that 200a fuse then? I'm going to be running a dual battery setup, do you not recommend to use fuses inbetween the 2 batteries either?