Big 3 Question

[Rashaddd 5,000+ posts]

So I'm out under the hood of my car prospecting doing the big 3 upgrade...and I realize its going to be a ***** to run any wires from my alternator to anything. The alternator is hidden under layers of wires/pipes/engine/exhaust pieces, and I doubt I'd be able to get to it without at least taking off the exhaust pipes coming off the engine block.

I looked at my alt and it says its just a 60 amp alt, so is there really too much of a reason to even upgrade the big 3 assuming I don't intend on ever replacing the alt in this car? Its a 2000 mazda 626 btw.

Also, if I don't upgrade them, and say only upgrade the ground wire to my battery, what would happen if I try to run a Hifonics bxi2607d? Rated at 2600 rms at 1 ohm.

I really don't want to put the effort into adding wires on my alternator if its hardly going to make a difference, but regrounding the battery is no problem.

Thanks for any input/suggestions

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[darkhunter139 10+ year member]

2600 RMS on a 60 amp alt?

Dont try it lol, big three or no big three for that many watts you are going to want to upgrade your alt and add an extra battery (And get a nice one under teh hood)

 

[Rashaddd 5,000+ posts]

2600 RMS on a 60 amp alt?
Dont try it lol

What if I'm only running it at 4 ohms though, ~900 rms

 

[darkhunter139 10+ year member]

What if I'm only running it at 4 ohms though, ~900 rms

You might be able to get away with that but will probably have a lot of dimming

 

[Rashaddd 5,000+ posts]

You might be able to get away with that but will probably have a lot of dimming

Alright, is there really any reason to bother upgrading alternator wires? I'd guess the stock ones should be able to handle 60 amps or almost that but idk

 

[darkhunter139 10+ year member]

Not 100% sure, dont want to give you false info so I will wait for someone else to answer.

It probably depends on the wire that is in there now really.

What kind of subs are you going to run?

 

[Rashaddd 5,000+ posts]

Not 100% sure, dont want to give you false info so I will wait for someone else to answer.
It probably depends on the wire that is in there now really.

What kind of subs are you going to run?

2 MJ 18's (8 ohm version)

The stock wire looks like 8 gauge, maybe 10.

 

[TurdFergueson2 5,000+ posts]

How are you gonna get 2 18s in that trunk?

 

[Rashaddd 5,000+ posts]

How are you gonna get 2 18s in that trunk?

Needless to say its pretty crowded in there, but I go sealed and I can fit a single 18 comfortably, with room for luggage, so I'm adding another one

 

[jrwalte 10+ year member]

2 18s and you're going to wire for 900RMS?! Forget it. Just a waste of money. Go with a single 15 or 18 and give it ~1000/1500 if you're looking for that loudness.

You may get away with powering a 15" at 1000RMS with that alternator with an upgraded battery and another one in the trunk (looking at ~ $400 just for those two batteries) and the big three.

Unless you plan on upgrading that alternator don't even waste your time with a single 18 let alone 2.

If you don't want to do the big three, look for a 10 or 12 and power it at ~500RMS.

 

[dman4486 5,000+ posts]

the stock wiring for your alt most likely can handle burst 60amp, but not sustained for any period of time

the idea is to get minimal resistance on the line to feed your amp as much power as possible

 

[Rashaddd 5,000+ posts]

2 18s and you're going to wire for 900RMS?! Forget it. Just a waste of money. Go with a single 15 or 18 and give it ~1000/1500 if you're looking for that loudness.
You may get away with powering a 15" at 1000RMS with that alternator with an upgraded battery and another one in the trunk (looking at ~ $400 just for those two batteries) and the big three.

Unless you plan on upgrading that alternator don't even waste your time with a single 18 let alone 2.

If you don't want to do the big three, look for a 10 or 12 and power it at ~500RMS.

They're MJ's...they only take 600 max so yea they'll be a little underpowered but they aren't exactly power hogs

I just love the lows of 18's, plus I think huge subs are just sick.

So: would running 800-1000rms @ 4 ohms be okay with a 60 amp alt? I can deal with dimming if thats the biggest issue I'll have, as long as I won't have issues with the amp and the car will run.

 

[jrwalte 10+ year member]

depends on how loud you go and what you listen to (heavy bass). Continuous 1000 watts at 13.5 volts would use apprx 85 amps on an 85% efficient amplifier. Considering you want to go with 2 18s that are rated @ 1200 it shouldn't be that hard to reach near 1000 real watts.

It's possible your amp will just shut off/fry due to huge voltage drops. A high end battery under the hood and something like a Kinetik HC2000 in the trunk may work.

If you like a lot of loud bassy music I would be prepared to need an HO alt of at least 120amps

 

[Rashaddd 5,000+ posts]

depends on how loud you go and what you listen to (heavy bass). Continuous 1000 watts at 13.5 volts would use apprx 85 amps on an 85% efficient amplifier. Considering you want to go with 2 18s that are rated @ 1200 it shouldn't be that hard to reach near 1000 real watts.
It's possible your amp will just shut off/fry due to huge voltage drops. A high end battery under the hood and something like a Kinetik HC2000 in the trunk may work.

If you like a lot of loud bassy music I would be prepared to need an HO alt of at least 120amps

Ok thanks for the advice. For the moment at least, I will just be running the single 8 ohm MJ off of a bxi2607d, so at 8 ohms it shouldn't do more than 500rms at the very most, which should be fine without any electrical upgrades at all, agreed?

I had 600-700 running through my old system and i didn't get any dimming or anything, not too much voltage drop even when playing test tones and stuff

 

[jrwalte 10+ year member]

Only one way to find out. At most you'd need to do the big three and replace stock battery.