My 95 Regal has the big 4 upgrade done. Battery to block, battery to chassis, battery to fuseblock, battery to starter. Didn't mess with the alternator wiring.

I have a 1600W Hifonics amp in there pushing a 1600W RMS 15" sub, with 2 stereo amps as well. My interior lights only dim on extremely hard bass notes.

The Bonneville on the other hand has a 900W Kenwood amp and a 500W RMS Alpine R12 with one stereo amp for the rear speakers, and the lights dim pretty badly under nowhere near full load and the voltage drops significantly.

My question is, what kind of alternator comes stock with the Northstar? Also, what kind of wiring is used to connect that alternator to the battery which is under the back seat? Somehow I'm doubting that its 2 gauge.

ACDELCO Part # 3341449 {140 AMP}

Haven't a clue what the wire gauge to Alt. is. Have you beefed the ground under the rear seat to body? It'* one of the most pathetic I've seen. Made a big difference running my twin Viair compressors.

Haven't beefed up anything yet. I'm planning on getting some 2 Gauge wiring run through soon, I just need to know what I need to replace.

Replace Ground lug to body for sure, I sanded off the paint under where the cheap crimped lug was, GM figures the threaded area of the hole was enough ground. Smeared a dab of No-Ox grease on the bare metal so it wouldn't rust. Knowing GM the Alt.charging wire is maybe 10% over the output. Maybe. They often close tolerance everything to the point of having to replace harness'*. #2 gauge? I'd be surprised to find it'* more 10 gauge wire.

That would be downright pitiful, and dangerous. Hell, the Regal came with 4 gauge wiring for the alternator from factory.

I'll try that first and go from there.

add more wire going to the alt for sure and fuse it with say 150 amp fuse since your alt is 140amp. i just say add and not replace since adding will be more flow altogether compaired to taking some away(factory wiring)

That thing has a 140 amp alternator? Wow...

I should have absolutely no problems with this sound system and lights dimming with that large of an alternator and an Optima redtop batery.

ya shloudnt have any probs but the system will only be as good as its weakest link. if the power wire going from alt to batt never got done then that would be the best spot to mod up. fuses arnt needed but a very good thing to avoid fires...which ive seen pics too many times in the past year lol