UNCLEBENZ

My lights flicker when I really turn up the volume and the bass hits - I have a JL Audio 500/5 Amplifier pushing two sets of component Q series MB Quart drivers and one JL Audio 10" sub.

What "size" capacitor do I need? 1, 1.5, 2, 3 Farad?

Any preferred brands?

Thanks for the help!

Fabrik8

Make sure you have a good battery first of all. The general rule of thumb is 1 farad per 1000 watts of power. Most of the brands out there are all fine, pick something that won't kill your wallet and doesn't have lots of blingy crap that you don't need. The more you pay for a cap, the more you've wasted paying for someone's marketing and advertising. Practically no one actually makes their own caps, they are all private labeled and there is a huge price swing for the same part from different brands. Don't bother with voltmeters, platinum terminals, and all that stupid shit, get something basic that does it's job.

Mount it as close to the amp as possible, with the shortest wire lengths that you can. An easy thing to do it just take your existing power and ground and run them to your cap, and then run short wires to the amp from there.

Also make sure that you have a large enough ground from the chassis to the battery, it's no use having big power cable and a bog ground back at the amp if the ground to the battery is undersized. You're trying to fix the weak links here.

UNCLEBENZ

Great info thanks -

Another question in reference to your comment about the battery. A good battery you stated - what is a good battery - High CCA?

Fabrik8

I like gel batteries like Optima Red Tops, they are lower internal resistance than common car batteries, which means more power faster. They can also take a beating from repeated discharge cycles, and aren't really affected by vibration over time like regular batteries either. They cost a little bot of $$, but they're well worth it.

They also start your engine quite nicely too..

Veritas

you always give really good info fabrik8.

but you cant go wrong with an optima

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If you do this you might not need a cap. I had 1400 reall watts, birth sheet to prove it, and all I did was use a yellow top and did the Big 3.

http://forums.caraudio.com/vb/showthread.php?t=124175

UNCLEBENZ

Damn, I just replaced the (stock 130 amp unit) alternator (with another)which was a PITA since it's below the drivers side head. I didn't think that it was going to come out.....

I will say that it was not as bad as the alternator that we replaced on Montmans old beater - I think it was a Honda Accord, an older model - that was an event!

The Optima Batteries - there are a few, red, orange, blue, yellow. Without having to do all that reading - is the "Red" top the best one?

Where do they sell them locally? I currently have a 550 CCA stock Motorcraft battery which I am sure is crappy compared to the Optima line.

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Yellow or red will do fine. I sell em through Interstate but Id have to call and get you a price. I know Autozone does too but I think they are alittle more. Thats a pretty good Alt. for what you have. Id say get a better battery and upgrade them wires to carry more current and you'll be fine. If you have anymore questons just ask.

fmstatic

i'm not a big fan of caps, so i'll offer a bit different advice. caps are like bandaids for bigger electrical problems.

first, improve your grounds if you haven't. i posted up a DIY on how to do that on an accord forum. different car, but same idea, so here's a link

other than that, either a battery or new HO alt will both help. unless your idling your alt is what your system is drawing from, so i would suggest upgrading your alt first but it's up to you, battery isn't a bad investment by any means

edit: k didn't read the whole thread, didn't realize geonfreaq had already posted a link to big 3. the diy he posted looks better anyways lol

Fabrik8

I'll have to take exception to that. Putting in a HO alt, keeping your old battery, and not getting a cap is a little backwards. Strengthen the important parts first, like the battery, because that's where most of your average power draw will come from. A cap will keep the local current spikes under control, and if you're maxing out what your stock alt can recharge, get a new alt.

Caps aren't band aids, they're really just to help with the light dimming. I do agree that the grounds are the first step though. The only other way to keep the light dimming under control is putting a trunk mount battery in.

The average power draw is all you're concerned about, and I don't think his amp is big enough to need a HO alternator. Getting a new alt is useless if you don't need the extra current capacity, so I'd try everything else first before trying a new alternator. The regulator on the alt can't respond anywhere near as quickly as a cap can, which is why a cap and a good battery helps with the light dimming. I think big alts are an expensive band aid to problems that can often be solved cheaper and easier first.

Red Tops are starting batteries, which is why I recommend them. Their internal resistance is lower than the Yellow/Blue tops which are deep cycle. A Yellow Top would be fine also (the blue top is just a yellow top with marine terminals) but in my experience they don't make as good of a starting battery under regular conditions.