Jump to content

Doing the big 3 (do I fuse?)


Recommended Posts

Hey guys, I started a topic a while back and got some awsome help.

I finally ordered the subs and amp combo and they should be here tomorrow according to fedex....

Meanwhile I just purchased a big 3 kit from sky high of 1/0 OFC. Running the grounds are no problem as I can add to these fairly easily and my one factory ground wire from the battery to frame is so small I couldn't imagine not adding to this one.

My one concern is running the new alt+ to battery+ with the big 3. Should I add a fusible link on this wire? Tons of debate everywhere. My current positive wires ( my mechanic that installed my alt used my original (4ga?). But doubled it up using 2 strands side by side on this connection. I don't like it and that's probably gonna get changed soon too but, These positive wires run from my original loom coming from the starter relay (that's how my car works) through a fusible link (not sure the rating but it's the stock one still so I doubt it's even 100amps. I'll look exactly what it is when I have daylight tomorrow. Should I add a fusible link to my new positive wire? If so what rating? I'm thinking 200 maybe? Or something lower so It matches the stock one already in place. OR do I need to upgrade the stock one too?? My alt is only 130amps. My amplifier comes with the standard 120amp fuse block to also install. 

 

Link to comment
Share on other sites

Typically when adding 1/0 wire from the charging stud of your alternator to the battery positive terminal the wire is rather short and typically able to be ran in such a way where the wire is never in real danger of abrasion causing a short or extreme heat from something such as the exhaust/manifold. 


Now you can fuse it if you are overly concerned about it not being fused and you will want to fuse it as close to your alternators output amperage. The vast majority of people don't fuse their positive wire for the "big 3" due to the reason I mentioned above and the reason I mention down below.

You will want to use an ANL fuse and fuse holder not a fusible link.
I think the largest gauge fusible links are around 8 gauge (maybe 4 gauge), but I am not aware of the amperage ratings they offer.
Using a 8 gauge or even 4 gauge fusible link on 1/0 wire will most likely cause a decent amount of resistance under high amperage loads and that's not ideal because it creates heat in the wire.
I'm more than certain your current fusible link for your starter is rather low amperage and rated for the maximum amperage that your starter draws when starting the vehicle. That being said it is fine and will not need to be replaced for a larger fusible link.

So if you have 180 amp alternator you can probably get by with a 150 amp fuse but if it blows use a 200 amp fuse, a 250 amp alternator then use a 250 amp fuse, if its a 390 amp alternator use a 400 amp fuse, etc. Try to use the closest fuse size without going over by too many amps, typically a fuse will allow a decent bit of additional current through for periods of times before it blows (which is why I said a 150 amp fuse for a 180 amp alternator). However like I said above it's typically not needed or done by almost anyone who does the big 3 upgrage.

 

 

Link to comment
Share on other sites

Thank you for the reply. Still waiting on fedex for my system. Hopefully tommorow i can do the full install. This is probably the best answer I've seen. I always figured fusing the wire was a precaution against a voltage spike/overload or something not as a precaution in the case of the wire insulation failing due to heat/abrasions. That makes sense why it would be optional. I plan to run my wires right next to the stock ones along the same route with zip ties so I shouldn't have any worries about that then.

Link to comment
Share on other sites

Thank you so much to everyone that has help me with the answers and reassurance I needed to get this done right. After fighting tooth and nail with fedex to get my subs, I've just spent the last 5 hours or so doing a complete install (minus the big 3). Most of that was running the wires the right way through the fire wall and doing it clean with little to no daylight. I think about 12:30am was my victory after minor trouble shooting. I don't have gains or anything set yet, just put a tiny bit (like barely any) on to hear it and holy shit. I'm cool with where it's at now lol, no real voltage fluctuation I think I dropped to 13.8 for a sec but it stayed at 14 or 14.1 for the most part during my short cruise And no dimming at all. I think My ancient halogen headlights are eating alot of that extra power but I'm converting to LEDS next and Still doing the big 3 just ran out of time and have work in a few hours, but that's the easy part now. I couldn't be happier with the outcome.

Link to comment
Share on other sites

13 hours ago, itsjeremy87 said:

Thank you so much to everyone that has help me with the answers and reassurance I needed to get this done right. After fighting tooth and nail with fedex to get my subs, I've just spent the last 5 hours or so doing a complete install (minus the big 3). Most of that was running the wires the right way through the fire wall and doing it clean with little to no daylight. I think about 12:30am was my victory after minor trouble shooting. I don't have gains or anything set yet, just put a tiny bit (like barely any) on to hear it and holy shit. I'm cool with where it's at now lol, no real voltage fluctuation I think I dropped to 13.8 for a sec but it stayed at 14 or 14.1 for the most part during my short cruise And no dimming at all. I think My ancient halogen headlights are eating alot of that extra power but I'm converting to LEDS next and Still doing the big 3 just ran out of time and have work in a few hours, but that's the easy part now. I couldn't be happier with the outcome.

Nice. Post a pic or two, or a vid even. Glad your happy

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...