MTV

In doing the Big 3 mod, I have seen the use of a fused connection between the Alternator and Battery to prevent an over charge. The 2003 Alternator looks to be 145 amps. what would be the right fuse to use with 4 gauge wire 150 amp fuse or lower? TIA

feeder82

Saccity's kit used a 100amp for what it's worth. I think it's overkill unless you're doing a big stereo upgrade

MTV

Thanks, feeder.

A stereo upgrade is actually the plan with one 100 amp subwoofer and one 50 amp speaker amplifier.

jim993

To protect the alternator, 145-150 amp fuse.

Speedy007

I highly recommend a 7 inch silk custom kenwoood 2 way
with a 3-3.5 inch tweet in the doors .. throw a 8 inch jbl and 600 watts at those bad boys and your now sitting front stage at any concert that comes through the speakers .. you don’t even need the rear left and right unless your looking to go def


add in a nice 6.5 7 inch 2 din . The 10 inch don’t fit well . If you go use a windows stereo u could tune on the fly ..

MTV

Thanks, Jim. I thought it was to protect the battery . . .

MTV

Thanks, Speedy. That sound stage would be over the top!

jdewolf

I would use thicker wire, 100A for 4ga. Maybe 125A for a short run.

knewblewkorvette

The MAIN reason you put a fuse on a power wire is because if you get into an accident and the power wire gets pinched (shorted), the fuse will blow instead of the power wire getting so hot it starts a fire. The fuse isn't there to protect your battery or your alternator, it's there to protect the car and possibly you. That being said, you want to put the fuse close to the battery, like using less than a foot of wire from the battery to the fuse. I always use 6". You want to use at least a 150 amp fuse.

Kingtal0n

Right ^^
On most cars, The alternator wire snakes to fusebox before it hits the battery and it has a fuse already in the fuse box. So adding a second fuse is silly.
Not to mention the alternator doesn't have the kind of capacitance a battery does or put out the kind of current a battery can in the event of a crash. And the fact the engine probably won't be spinning at that point either. The vehicle should have some kind of inertia switch for the fuel pump if the wreck is that bad anyways.

Its the big giant wire coming off the battery headed for the starter than need the fuse because... it isn't fused from the factory. Thats the wire that gets pinched grounds the battery out and starts a fire.

Its a much bigger concern for battery relocations which often run very long large gauge wires throughout the chassis.

C5MSG2004Vert

The alternator's regulator and alternator's output wires both have fusible links at the starter. This protects the wiring and alternator. The alternator has a failure mode that is a short circuit or low resistance and can actually cause the alternator and wires to burn if enough current flows. So if you add a new wire it should be fused or use a fusible link.

MTV

BIG Thanks to all the Corvette Brothers who have contributed to my understanding (and confusion) of automotive electronics !