headlights dimming again

Ok I'm still havin problems with my lights dimming. I re-did my amp ground I have 2 explode amps the grounds run to a distribution block and I ran that to the chasis of my car. I did the big three I ran positive alternator to positive battery terminal. Neg battery terminal to chasis and alternator mounting bracket to chasis . I did the big three with 4 gauge cable and I think that's were I went wronge but idk. My cap drops from 15 to around 11.5v while I'm playin my stereo and climbs back up to 15v when I turn the volume down, please help. Would this all go away of I simply replace the 4 gauge with 0awg

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Db electrical 200a alt
0awg wiring kit
Yellow top optima
2 pioneer premier TS30004DVC subs

I'm sorry I have a 99 grand am and a cheap Sony head unit

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Db electrical 200a alt
0awg wiring kit
Yellow top optima
2 pioneer premier TS30004DVC subs

No. The car and deck have nothing to do with your issues. Your issue is that your alternator is too small... That's the part that needs upgrading now.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

But I just bought a db electrical 200a alternator your satin it's too small?

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Db electrical 200a alt
0awg wiring kit
Yellow top optima
2 pioneer premier TS30004DVC subs

You hadn't mentioned a new alternator.

#4 is too small for 200A. You need a #2 at least for 200A. Make sure it is fused as well, (at no larger than 225A) JUST as you fuse every large gauge cable connected to your battery.

What amplifiers do you have? What is their real-world power capability? (Not their ILS (if lightning strikes) rating, AKA "Sony watts"...)

What is the condition of your grounds? I know you said you had upgraded the cables, but did you address the connection point itself?

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Ihave no clue what the rms is on my 2 sony amps.  there max is 1000 ( i know thats B.S.) .  As far as the ground when i re did them i switched places too, i had the amp ground in the trunk bolted to the strut tower but i was told my car was a unibody car so there is no true frame on it.  so i bolted the ground directly into the strut tower ( instead of using one of the strut tower bolts i ran a screw right into the metal sourounding the strut tower)  and under the hood i have the big three upgrade but i only used 4 gauge.  i went from negative battery terminal to what i think is the chasis right by the battery ( i made the new hole rigt by the factory ground) i sanded it all nice so its on bare metal.  then i ran a wire from the alternator mounting bolt to again what i think is the chasis.  its the same peice of metal as the battery ground that i previously explained.  and of course a wire from positve battery terminal to alternator positvie.  Im pretty certain i have enough power to run those sony amps, i just cant seem to get the grounds right.

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Db electrical 200a alt
0awg wiring kit
Yellow top optima
2 pioneer premier TS30004DVC subs

Reset your grounds... This is where I would go as a next step...

How badly ARE the lights dimming? Is it a severe dip, or just "a little noticeable"?

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

i was told not to run the grounds to a distribution block, but to ground the amps seperately with the shortest amount of wire you can get by with

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There dimming bad ( no system at night) I didn't know about the distrabution block I just thought it was easier



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Db electrical 200a alt
0awg wiring kit
Yellow top optima
2 pioneer premier TS30004DVC subs