capacitor vs high amp alt

**midnightnavyz28** · 09-23-2008, 08:10 AM

I'm currently running the JL Audio 300/4v2 & Jl Audio 250/1v2 amplifiers (professionally installed using 4 gauge power and grounds), with a brand new duralast gold battery. My lights at night are pretty dim and blink at high volume...correct me if I'm wrong, but aren't capacitors used to keep the amps powered at peak voltage?...not so much to stop dimmed lights?...if thats correct i dont need a cap, 1) jl's slash amps keep themselves powered well 2) thats not gonna solve my light problem....so would a new high amp alternator (160 amp??) and some bigger lead wires for the alt. fix the problem?...sorry for the long post but i work 3rd shift so i dont like the idea of driving my Z28 in the dark with deer running wild everywhere

**bigrondownhiller** · 09-23-2008, 01:49 PM

A capacitor will help but might not solve it completely if your amps draw a lot. A higher amp alternator will help the best. Just be sure to check where it makes higher amperage. If it peaks too high you still wont get enough juice.

**midnightnavyz28** · 09-23-2008, 04:46 PM

Yea, the alts. I've seen put out less power at idle than a stock 1 and don't wind up until 2000 rpms..... Do you know of any specific alternators that have power at idle? Price isn't an issue as I've already invested over $3,500 in my system ....THX!

**bigrondownhiller** · 09-23-2008, 05:09 PM

check powermaster and paperformance.

**MnLS1** · 09-25-2008, 07:12 AM

id try a capacitor and beefing up the guage wire from you alternator to battery and ground.

**wenn_du_weinst** · 09-25-2008, 12:41 PM

a cap is a waste most of the time they make it worse because the discharge all of the power they store in less than a second then the alt got to keep up with the amp and the cap try getting the biggest kinetik or powermaster battery that will fit under the hood and upgrade all of the power and ground wires around the alt and battery and also try moving your ground a better spot and make sure there is no paint under the ground

**predator** · 09-25-2008, 03:35 PM

money isnt an issue? Mount an extra battery in the trunk...

-me

**The Project** · 09-25-2008, 10:53 PM

Originally Posted by wenn_du_weinst

a cap is a waste most of the time they make it worse because the discharge all of the power they store in less than a second then the alt got to keep up with the amp and the cap try getting the biggest kinetik or powermaster battery that will fit under the hood and upgrade all of the power and ground wires around the alt and battery and also try moving your ground a better spot and make sure there is no paint under the ground

I agree.

A cap really is a waste of money. start with the big 3 and see if that helps.

Also, a really big (180amp) alternator will produce LESS amps and low rpm's that a stock or 120 amp alternator. Bigger is not always best. A bigger alt. works if you do a lot of highway driving but not so much in traffic.

Two batteries and an isolator will definitely help....but I'd start with the big 3 first.

Good luck.

**squee** · 09-30-2008, 05:06 PM

I'd personally get a Optima (deep cycle battery is a wise investment on a good stereo), a larger alternator pulley (forgot who, but one of the major brands makes one), and upgrade all the wiring. If that doesn't do it, add a second battery.

**F55c6** · 10-04-2008, 02:27 PM

I have a Rockford 2 Fared capacitor and I still need a larger alternator especially with the ac on and at idle. I just purchased a Powermaster 150 amp alternator and will be putting it on Thursday. I'll see if that takes care of the draw.

**02WS6dream** · 10-07-2008, 10:44 PM

I originally bought a cap to solve this prob, and it worked in that car and i have included it in my setup in each of my 2 cars since then with no probs. You may be drawing more current than i am/have; I don't know, but for the $$ it can't hurt to try it first. It sure doesn't hurt any. And yes, it does discharge AND recharge rapidly; that's what its for. During music peaks it discharges to keep consistent power, and recharges quickly. Your lights likely dim to 'the beat', or at momentary peaks, which a cap may be very well be able to overcome. Money may not be an issue, but no reason to throw it away!

**Carlos01SS** · 10-08-2008, 12:37 PM

I still have dimming in my car, I got 1600 watts rms being pulled from my Optima yellowtop battery, got 2 4ga. wires coming from the battery to the 3-farad cap, and I also have a 220 amp alt.

I have heard that the Big 3 wiring mod is the best thing to do, so I'm going to do that too. Lots of folks who have done the Big 3 wiring have praised the results, so that's the next step for me.

**bigrondownhiller** · 10-08-2008, 01:56 PM

Originally Posted by Carlos01SS

I still have dimming in my car, I got 1600 watts rms being pulled from my Optima yellowtop battery, got 2 4ga. wires coming from the battery to the 3-farad cap, and I also have a 220 amp alt.

I have heard that the Big 3 wiring mod is the best thing to do, so I'm going to do that too. Lots of folks who have done the Big 3 wiring have praised the results, so that's the next step for me.

You didn't upgrade the wire from the alternator to the battery after the alternator install?

**Carlos01SS** · 10-09-2008, 08:39 AM

Originally Posted by bigrondownhiller

You didn't upgrade the wire from the alternator to the battery after the alternator install?

Nope, I was kinda hoping that the new alternator would have solved the dimming of the lights, but no such luck.

**mbrownin** · 10-09-2008, 09:59 AM

Originally Posted by squee

I'd personally get a Optima (deep cycle battery is a wise investment on a good stereo), a larger alternator pulley (forgot who, but one of the major brands makes one), and upgrade all the wiring. If that doesn't do it, add a second battery.

Larger alt. pulley will make the alt. turn slower.