Got some extra 0 gauge wire that my buddy doesn't need so am doing a big 3 upgrade on my 90 crx (stock 94 integra alternator 90 amps) what size inline fuse do I use? its going from the alternator too the battery.


Thanks for the help guys

 

Where do you want to put a fuse? I didn't use any fuses for my big 3

 

Your using 0 gauge cable to connect a 90 amp alt. to the batt.?

Did you know that 8ga cable has a capacity of 100A, [that's 10 more then that alt. will ever put out] kind of makes the 350A 0ga way overkill.

The in-line fuse you put on any lead should be what the lead will handle, 8ga=100a fuse, 0ga=350A fuse, the fuse is there to protect the lead, the fuse will blow when load reaches/exceeds current, [amps] capacity of lead.

Upgrading main powers and grounds can't hurt, however there is a point of diminishing return.

Unless you have installed a load that draws close to 350A of current, I see absulutly no need for 0ga cable. 94

 

am getting the 0ga cable for free, I plan on upgrading the alternator in the future. so you are saying that installing this cable will hurt my system?

 

between the alternator and the battery.

 

It will not hurt anything, it just over-doing it.
Kind of like using a 45gal barrel to carry 5gal of gas, can't hurt but a 5gal jerrycan would work just as well. 94

 

You'll be fine without it. I've had mine setup without a fuse for over a year and no problems


As far as overkill, it's MUCH better to have overkill then underkill. You could run 4 runs of 1/0 and have zero problems, but run 8awg for a bigger system and watch how nothing will worth properly... I use 8awg power wire for speaker wire in my setup

 

How much current are you running that you need 8awg? I have never had a problem using 14... or even 16 on most systems.

 

Same, 8 here as well

 

Why? Did you have your 14 gauge burst into flame?

 

Honda actually used to use one of their links in the fuse box for the alternator, the reason for the fuse, is if something causes a dead short in the alternator, bad diode, winding shorted etc, it does happen, it stops the battery from melting the alternator lead when it shorts to ground.

 

Then you've never installed a big system. Obviously the less resistance the better right?

The stock alt wire runs to the fuse box, which is still there on my car. I just added the 1/0 and ran it straight to the front battery. I know things CAN happen. I can slip off of the sidewalk, crack my skull on the curb, and bleed out in the street. Does that mean I shouldn't walk on sidewalks?

 

no one is saying you shouldn't walk on sidewalks, why wouldn't you do something as simple as add a fuse? it's not that big of a deal, but it may keep your car from burning to the ground.

 

As I said, there is a point of diminishing return, if you do not have anything, [load] that draws 350A of current then you do not need 0ga cable, there is no "less resistance" by using the proper gauge of cable.

A fuse should always be installed to protect the power lead, and your car, a 0ga cable connected to a 450CCA batt. will not just burn out it will get red hot, burn off the insulation and ignite anything flammable, your car.

You also do not intentionally walk right on the edge of a sidewalk, just because things can happen does not mean you just ignore things that could prevent that thing from happening.

Here is something to think about, if your 1/0 cable shorts out and your car burns to the ground, do you suppose your insurance carrier will cover it?

Absolutely not, so think about the advice you give people...
"You'll be fine without it. I've had mine setup without a fuse for over a year and no problems"
just because you have not had a problem "YET" does not mean you won't. 94

 

^^^ wow. I can't beleive he said that. No fuse, lol. Luis. Get yourself a anl fuse holder and fuse it to your alternator output and call it a day. I have to agree with fcm. Its a over kill but if its free its free.

Are you trying to out bump my car?....... I thought this was a race car, lol. Whats going on here?

 

as far as fuse size If am understanding correct fcm recommended a 350a fuse. And about out bumping your car I dont have the budget for that. lol
thanks for all the info fmc and des

 

Its cheaper to get a 100 amp as you not going to be pulling anywere near 350a in your car. Fuse for the alternator ouput.

 

But AC behaves differently than DC, with the skin effect showing in AC installs. Now granted that's mostly in higher voltage/amperage runs, and is more pronounced at higher frequencies than lower. Just something to keep in mind (and using a larger stranded wire that doesn't have each small strand isolated from each other still appears as a single solid wire to the AC signal)

 

Ditto the above^^^

Although you should never install a bigger fuse then the cables capacity, there is no problem installing a lower amperage fuse, in your case with a 90A Alt. I agree you should use a 100A fuse.

If you upgrade the alt. in the future, you can replace the fuse with an appropriate one. 94

 

Well I guess I've done everything wrong according to you guys. But I'm willing to bet alot of money that if I downsized my wiring and fuses, my clamped power would decrease and my tl score would go down.

And I'm guessing 3 group 31 batteries and a 140amp alt all for a single 1500 watt amp isn't needed. But with 1 group 34 battery my voltage drops to mid 11's but with my "overkill", I don't stop below 13.5

 

thanks for the info..........

 

At what rpm does your alt put out power?

 

My voltage drops that low at idle. While driving, I'd be surprised to see it drop below 14.0

 

if you don't want to run fuses and set your car on fire, go ahead, but don't tell people that's ok, and don't park near me, things do short, cars do catch fire, you must not realize how much potential is in your batteries. I've personally seen cars burn to the ground because people put in a system and knew it all.

As far as the original poster, it has nothing to do with having a huge system, he has a 90 amp alternator, he doesn't really need wire that large or a fuse over 100 amps. If it was me, I would run some quality 4 gauge,that's plenty to handle most alternators, and gives a little extra capacity to account for loss in the wire.

 

x2.

I usually still wire with 0 or 4 just incase of upgrades. Rewiring is a complete bitch.