Hi there.. I'm running two 10" JL 10W6's with a JBL 600.1 amp. Now, I realize that .5 - 1 farad should be sufficient. Was wondering if there is any benefit of overkilling with say 3-4 farad's, since I can get it for almost the same price. I have a new alternator under the hood, but I'm still getting some light dimming when the bass punches with the vehicle accessories on.

Justin

It'll never hurt to go higher than you need, especially if you can. The amp will still suck the same ammount of power from either cap, it just depends on how much. Plus, then you wont need to upgrade later.

If you're only running 600 watts and the lights are dimming, then I would look elsewhere for the problem...

How many Amps is your Alt.? What kind of car? Any other amps in the chain?
But as far as a cap goes, they are ONLY bandaids, they 'solve' nothing, only attempt to hide the problem... Take a closer look at your electrical system, and make any improvements that you can, rather than using a cap.


Mark

Have you upgraded the factory ground under the hood, from the battery to the frame with some 4awg wire, that is a good start, also.

wasted911 - Thanks for the reply.

SQ civic... it's a BMW e36. Unfortunately the increased power draw is coming from a load of other mods in the car sucking up power. I understand a capacitor will not solve the amperage fluctuation, but it will solve the voltage fluctuation---which is my primary concern. Not as much because of the dimming lights, but because I have a lot of sensitive electronics in there, would like to minimize strain on the voltage regulator, and keep the voltage trickling into the battery constant. The amperage fluctuation I guess I can't do too much about without dropping loads of cash.. so this band-aid seems like a suitable solution for my needs.

Are there any downfalls to having say a 3 farad cap?

2 8's AKA Jeepbeats - I didn't upgrade the factory grounds, but that really is a smart idea. Thanks for the advice. Is there any benefit of upgrading the ground on the alternator as well?

Justin

A lot of people do the big three: http://www.canadiancaraudio.com/cgi/...c;f=3;t=011293

Hope that helps! Welcome to the board, by the way.

What other mods have you done to the car that are sucking that much power?

Mark

some capacitance along the line will help with instantaneous Vdrop.. but the larger caps suffer from high ESR... some so outragious that your $2000 carbon cap from RF is totally NFG for the application.. yet people still buy them... [img]graemlins/freak.gif[/img]

I wouldn't go any higher then 2F in one shot, and a pair of 1F cans would probably be 4X better...

Good information to know... is there an actual 'rating' or 'number' I should be looking at that gauges the ESR?

These are the specs of the cap I'm looking at:

Capacitance: 2,000,000 micro farad (2 FARAD)
Working Voltage: 16DC
Surge Voltage: 24DC
Equivalent Series Resistance: 0.0015 ohm @ 120hz/25 C
Capacitance Tolerance: +- 10%

[ January 24, 2006, 11:47 AM: Message edited by: Justin_Toronto ]

well .0015 ohm is generally considered to be pretty standard for a good 1F cap... the one you posted is a 2F so if that # is accurate it sounds pretty good...

Some manufacurers will cheat the rating though... so be warned...


A good battery will generally have an ERS around .02-.04 ohms by compairison