Car audio guys
Need a little info. I have a 89 Jeep Cherokee, working on putting a system together to drop in it (already has db drive speakers all the way around). I will have 3000 watts RMS in my sub, along with a 2500.1 mono block amp. I plan on using 2 gauge wire, doing the big 3 upgrade with 0 gauge. Question is ....is this the point of upgrading the alternator and battery? If so, how do I determine the output I need? Thanks for any and all help in advance
2007 Civic FA1 and 2005 Yukon XL Denali
Start by putting a 1 farad or greater capacitor in line on your power cable. That will help tremendously with your power demand for an amp that size. If you absolutely need a battery, look into an Optimal yellow or blue top.
Originally Posted by Echonova
If you are really worried about the amperage draw of the amps, you could install a second alternator(high output) to run the whole system. Stinger makes kits for just about any vehicle. A lot of high output alternator go up to around 250 amps. But leave the factory alternator to run the vehicle. Have the second alternator run a second battery, like a yellow top that was referred in the post before this one. Then the system ran of the yellow top. You won't have any problems with that setup. No lights dimming or b.s..... and a dedicated alternator and battery specifically for the system.
Bacon...I have a SQ 2 Farad cap....it does help(in older cars at least) with the lights and such. But my issue isn't just lights, it's over working the OEM alternator and straining the electrical system... Depriving the amp of power and killing a battery.
Berta...If I go that route I won't be on a budget SPL build lol. If I go to that extreme I will be getting some SMD subs and such. This setup is one sub and one amp, in a ATREND SPL box. Had the same setup with one 10" DB Drive k5 (625 RMS)and it hit really hard....Stepping up to a single 12" sub with 3000 RMS, 6000 MAX. (advertised anyways lol)
2007 Civic FA1 and 2005 Yukon XL Denali
There is some companies that make budget high output alternators. I used one on my 96 Tacoma. With a stinger 5 Farad hybrid cap.
Went from a 65 amp to a 175 amp alternator. Bought it off eBay(seller was from Texas - actual alternator company) for around $150. This settle my problem. This is about as budget as I can think.
I still have that cap for $50 shipped.
Hell yeah I will keep that cap in mind.....just spent a good bit on box, wiring and sub....whats your location?
2007 Civic FA1 and 2005 Yukon XL Denali
Macon area.
A cap is an old school bandaid. If you're really putting out that much power, your current draw is going to be astronomical. You need a built alternator, no questions asked. Once the vehicle is running the alternator is provided all the power to the vehicle. Also, why run a 2AWG wire when:
1. It's not a common car audio gauge.
2. You're already doing the big 3 with 1/0.
The rule of thumb for capacitors is 1farad per 1000watts.
Capacitors are are NOT a solution for an underpowered alternator. Do not use ones with voltmeters on the top, their high ESL will render them useless
They were sold out of that sub and don't sell it anymore. I have already wired it with 0 gauge wire, the big 3 with 0 gauge wire, got the SPL box....ordered a Bosch 100 amp alt, and an Optima yellow top. For now I have a Quantum 12" 3000w/750w that is going in for now. Just gonna save some money and go with 2 DB Drive K9's, that'll be 2000 watt RMS.
Note: I know Quantum is lower end.....I also know DB isn't the greatest, but its great for the price and I can get them through a friend at good prices. I have looked at Sundown and just can't get the same RMS for the same price.
2007 Civic FA1 and 2005 Yukon XL Denali
^^^^ this
[1996 Integra GSR]
[Still not running]
Also the cap isn't supposed to be a band-aid.....hints why I upgraded my alt and battery....it's just there to help the amp have the power it needs consistently
2007 Civic FA1 and 2005 Yukon XL Denali
Do you not realize the contradiction? Let me first start off by saying that I'm both a professional mobile electronics installer and an electrical engineering student, so I know just a little about this
I'm going to express a few concerns and I'll even use some basic math to back it up.
Primarily, despite what you may think your alternator is still insufficient. Although you have upgraded to a 175A alternator, you will still not be producing enough current to support the original demands of the vehicle, the new load you have presented with the sound system, and have the proper headroom to allow the alternator to live a normal life. Let's say you end up with "only" a 2000 RMS setup like you mentioned earlier. At 12.4V-14.4V (assuming the alternator you selected is going to make it to 14.4V with that much load is an optimistic assumption) you're going to be drawing between 140-160A just to run that amplifier. Even if that was the sole load, at 140A (the best case scenario in this example) you would already be at the maximum load for healthy alternator life which is 80% of current capability. Now once you add on the original requirements of the vehicle you're well over 100% current capability which means you've maxed out the alternator and are now dipping into the battery. So not only are you killing off your new alternator, but also your new battery, which leads to my next issue.
You have selected a deep cycle battery, which is fine for low voltage situations such as listening to music with the car off. However, a deep cycle battery requires more time to recharge; this is the trade off for the deep cycle capability. With you already dipping into battery voltage because of the insufficient alternator, you're making it even MORE difficult for the battery to recharge. The battery's true function is merely to provide power to crank the car; once the vehicle is running the alternator has 100% responsibility to provide power to the car and recharge the battery for the next crank. The deep cycle battery is offering you no real benefit in this scenario, you're making it harder on your electrical system. For a normal system, a deep cycle would allow some extended listening without much issue and would be able to recharge fine assuming a sufficiently long commute. However, the demands of your system greatly exceed any benefit a deep cycle would offer in such a case. For the electrical load your system presents you will be listening to music with the car running every time. Therefore, we get back to the issue that your alternator is insufficient and your capacitor is a bandaid.
Please take from this information what you will, I'm merely trying to offer some professional advice to help you in the long run.
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