Big 3 wiring upgrade, couple of general questions seeking specific answers.

[Eddo Rogue]

I want/need to do the "big 3" wiring beef up job.... and seeking some pre-attempt feedback.

First off this is a 4.0 ohv, running stock 95amp alternator. I plan to run an explorer 130amp to power a few extra things.

I plan to add an electric fan, some lights (small lightbar and some lil square LED's, nothing crazy), and maybe eventually a small stereo, like well under 1000w. Maybe even just a 200w subwoofer.

Will 130 amps be enough for the above mentioned? or bite bullet and go for 200+ amp bad boy?

What else should/can I rewire relatively easily besides the big 3 ( +alt and battery cables and the grounds)?

Also....

What gauge wire would you recommend? Whats the best wire out there as far as continuity, flexibility, heat/weather resistance, insulation etc....Stereo/audio stuff? Welding supply stuff? Marine stuff?

Where and what size fuses should I use? I'd rather go overkill w/ fuses/relays than risk a meltdown.

Any battery terminal recommendations?

Anything else I should know will be appreciated. Pics would be awesome.

I have read many threads on this topic from various forums, and ended up with a mountain of questions....hoping this will reduce it back down to a molehill of a few wires, connectors and fuses.

 

[Curious Hound]

I’ll start you off with simple facts. Watts = Amps X Volts

130Amp alternator X 12Volts = 1560watts maximum at maybe 2000rpm or above.

That is to power everything that is running simultaneously. Momentary loads above that can be handled by the battery. But its not wise to design your system to be operating at maximum capacity all the time. Plus, that capacity is reduced at lower engine rpm, especially at idle. others with more experience n the car audio realm will give you more specific guidance. I will say that a 1000watt amplifier is rarely using 1000watts. That is a peak power rating that would occur when a loud spike of sound is produced with the volume knob turned to the max setting. So, what percentage of that do you design your system to handle? I don’t know. I value my eardrums too much to worry about that level of sound.

 

[Eddo Rogue]

I’ll start you off with simple facts. Watts = Amps X Volts

130Amp alternator X 12Volts = 1560watts maximum at maybe 2000rpm or above.

That is to power everything that is running simultaneously. Momentary loads above that can be handled by the battery. But its not wise to design your system to be operating at maximum capacity all the time. Plus, that capacity is reduced at lower engine rpm, especially at idle. others with more experience n the car audio realm will give you more specific guidance. I will say that a 1000watt amplifier is rarely using 1000watts. That is a peak power rating that would occur when a loud spike of sound is produced with the volume knob turned to the max setting. So, what percentage of that do you design your system to handle? I don’t know. I value my eardrums too much to worry about that level of sound.

I am educated on the fundamentals and that basic equation, but will admit I am rusty on the math, and you just did it for me so thanks lol.

I think 130 amps will be plenty, especially since I will never run everything simultaneously, if rarely at all even individually. Really my only concern is the electric fan, and mainly just its startup draw.

Also I am not so savvy on wires...like what gauges handle what loads, resistance per thickness/length etc...

So far Im leaning towards 2 or 4 gauge wire, ideally something flexible and heat/waterproof, and 150amp main fuse should suffice.

Also my hearings already shot

 

[Eddo Rogue]

I forgot to add this all started when I installed a new (not reman) Bosch 130amp alternator, on which the bearing quickly crapped out, and it blew the 15 amp fuse in my main box along the way. Ive been running my original 95amp since (which I luckily saved)

Also the starter relay/ wires are really hot when running. I may even replace the starter relay just because it looks old.

 

[Curious Hound]

There are some charts online to guide you in wire size. I don't have one handy at the momnt. Especially on DC, the length of the wire plays into the size because wire does have resistance. So, as current in the wire increases, its current carrying capacity decreases. The wire itself will “drop” some of the voltage and your load device will then receive less voltage. Its a self-feeding cycle since the power used within the wire causes heat. Hotter wire has higher resistance than cold wire. So the problem gets worse. Most of the larger wires in a vehicle are pretty short So this effect is minimal.

Again, momentary spikes in current aren't as bad as long term high current.

 

[Eddo Rogue]

There are some charts online to guide you in wire size. I don't have one handy at the momnt. Especially on DC, the length of the wire plays into the size because wire does have resistance. So, as current in the wire increases, its current carrying capacity decreases. The wire itself will “drop” some of the voltage and your load device will then receive less voltage. Its a self-feeding cycle since the power used within the wire causes heat. Hotter wire has higher resistance than cold wire. So the problem gets worse. Most of the larger wires in a vehicle are pretty short So this effect is minimal.

Again, momentary spikes in current aren't as bad as long term high current.

I dabbled in it, will need to study more later. Yep what you said is why I am concerned about thickness/length, I think its one of those things where overkill can cause problems, just like not enough...

 

[Curious Hound]

Overkill just increases cost and weight.

 

[RonD]

Overkill just increases cost and weight.

And police can get involved, unless you get rid of the bodies

 

[Eddo Rogue]

And police can get involved, unless you get rid of the bodies

A friend will help you move. A best friend will help you move a body.

 

[Eddo Rogue]

Ok so now Im wire shopping....found everything from cheapo chinesium kits to multi hundred dollar Rockford fosgate kits. I think based on my efan experience. It will save my time, money and headaches doing a lil homework and making my own kit. Looks like most kits are 2/0

 

[bobbywalter]

What fan? 8 to 10 gauge is good for many.

 

[JOLENE_THE_RANGER]

prowireusa.com is the best place to get professional Motorsport wiring supplies. depending what fan you use and what your fans peak amp draw is youll wanna stick to about 12G. good quality Motorsport wire is important.

 

[Eddo Rogue]

What fan? 8 to 10 gauge is good for many.

FFD dynamics fan, I was thinking 4/0 or 2/0...not sure what gauge that is, I'm a lil confused about the various forms of wire measurement thicknesses that exist....FML

 

[Eddo Rogue]

prowireusa.com is the best place to get professional Motorsport wiring supplies. depending what fan you use and what your fans peak amp draw is youll wanna stick to about 12G. good quality Motorsport wire is important.

Awesome thanks I'm looking for good sources, will check them out.

 

[Curious Hound]

The FFD 16" fan is only rated 9 amps. That's not bad. Comes with 14 gauge leads. So 14 or 12 gauge wire to supply it, 12-15amp fuse.

4/0 or 2/0 wire is pretty huge. For 135 amp alternator, I would probably use 4 gauge wire for battery ground and alternator-battery cable. 6 gauge would probably be ok if the cables are really short.

Wire seizes are weird. Starting at 0, the wires get smaller as the number gets bigger. So 4 gauge is bigger than 8 gauge. When wires need to be bigger than "0", they add more 0's. So 2/0 is bigger than 0. 4/0 is bigger than 2/0, etc.

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