Hi not sure where this thread belongs... couple questions about aftermarket stereo install, factory wiring, and aftermarket alternators.
Basically my problem is that i am getting voltage drops (dimming headlights) when my radio is somewhat loud (mostly bass hits) I have 2 amps drawing about 1k watts of power, the wiring is all Rockford fosgate power 4guage fused, and connected to the battery which is conviently in the back of the car (i love my magnum) ground is going directly to the neg terminal on the battery.
What i'm looking for from you all is for someone with a similar/higher power setup that has no voltage drops/ or overcame them :D I have checked some audio forums and have been advised to upgrade the "big 3" factory wiring (neg battery to chassis, engine to chassis, alternator to battery positive) to the largest guage wire i can afford, and if that dosent solve my problem to look into a larger output alternator. I have some 0/1 guage wire in the mail to do the upgrade to the first 2 spots i mentioned, as the alt <----> bat + is rather long/unexciting to install :( It also looks like a rather large guage wire to begin with. Have any of you upgraded these wires, know the guage of the alternator to bat +, or upgraded your alternator and if so to what and from where :)
I'd appreciate any response/advise/criticism/help/flame or just to hear that someone else is having/has had the same issue. thanks in advance :)
djc208
03-21-2006, 10:45 AM
While none of that stuff will hurt I don't think it's the limiting factor, after all that wire carries all the current needed to spin the starter motor. The magnums already seem to have issues with the lights dimming based on engine/electrical load. I've noticed it in my R/T and I'm running the stock stereo.
My limited knowledge of these systems I would think a capacitor of the appropriate size is what you're looking for. The bass hits require spikes in power demand that put a large but momentary load on the electrical system which can't compensate fast enough to keep up with the rapid swings in demand. The capacitor helps to even out these swings. I should think that would solve the dips in your lights.
magnummitch
03-21-2006, 04:27 PM
In my prior life.....I was a highend custom audio system designer/builder for one of the major electronic retailers for 10 years. I agree with DJC, look into adding that cap before you go thru all the headache of rewiring the car. Do you have any engine noise while this is happening too? If so, I would suggest grounding the amp to the sheet metal/chassis and not the battery itself. When the other audio equipment is pulling the ground from the chassis and you are pulling your amp ground from the battery, it can make for a 'floating ground' problem and cause all sorts of wierd behavior in the system as a whole. I have not actually cut into my magnum for a system.....yet, so I have not actually experienced your problem, but I would try that cap before I did anything else.
Another thought, how many subs are you running, what is their impedance and are they series or parelled? If you parallel 2-4 ohm speakers, the amp sees that as approx 2 ohms. Low impedence=less sound quality, louder volume, harder on the amp, more current draw;ie, dimming lights. If you have 2-4 ohm subs, it is better to run them one to each channel than bridging the Fosgate amp down to one channel. (better for the amp sake, anyway)
Good luck!
Eli
03-21-2006, 05:09 PM
I to have noticed the dimming lights with the stock setup, i had originally orderd a 1f cap when i ordered all my other pieces, had to send it back cuz box was broken into by UPS :( it was missing the screws to attach, so i sent it back, try w/o it... guess i'll get another cap sent :). Thanks for the info mitch, yeah i do have noise, which i also decided was from the wiring at the battery, when i get those 0/1g wires i'll hook my ground up to a separate chassis location from the dist block. To answer your question, just a modest setup i'm not into SQ or SPL just like it louder then stock. 1 15" xplode (yeah its cheap but i can barely tell good from bad in a sub ) 4ohm svc. run unfortunately no off a fosgate amp, just the wiring is fosgate, the amps are infinity 4ch and currently using a temp amp for the sub sony 2ch bridged to 250w sub takes 450. I was thinking about upgrading to a class D mono amp around 500w to give the sub more life/hit. but i wanted to get the noise/voltage drops out of the way first. Cap is ordered, hope it helps :)
hattey
03-22-2006, 08:40 AM
a cap is not the way to go, you need to start with a higher cranking battery. The problem is that because dodge put the battery in the rear, and just made a long run of wire to the front of the vehicle. the wire looses alot fo current to get there. They also used a battery (at least in my RT) that was not of sufficient power for what it needed to handle. The first thing i did when i bought my magnum is replace the battery with a Stinger Power2 1700 Dry Cell Battery. I picked it up at cost becuase i work at a stereo shop, but they retail right around 350. The battery is a perfect replacement because it is virtually identical in physical size, but it offers 1700 peak cranking amps, and almost 1000 cold cranking amps. After this 5 minute install, my lights no longer dim. The car also starts easier and quicker.
Thanks Guys
hattey
Eli
03-23-2006, 01:10 AM
i was pondering a new battery as well, in my last vehicle i used 2, 1 front/1 rear and never had voltage issues, used yellow top optima, how does that compare with the stinger2/stock? (lol i'm to lazy to look it up). Thanks hattey!
04_on_22s
03-23-2006, 01:57 AM
Caps are generally just a band-aid to a problem. I'd rewire the vehicle first with 1/0 and replace the battery. I have used Infinity 4 channels before in customers rides and I'd say 50% of them pick up some sort of noise. I have had to resort to selling my customers the cheaper RCA's and wrapping them myself with 2 layers of foil to block any chance of the amp inputs from picking up any noise. Good luck on your project.
hattey
03-23-2006, 08:02 AM
The stinger batteries are better in a couple of ways, they have more life cycles at each drain level, so you wont have to replace it as soon as you would with an optima, also, because it is made by the same company that does all of your stereo wiring, it is designed with the ability to do thinks like change the terminal styles, etc.
ScojoDak
03-23-2006, 10:38 AM
Try looking at this thread from SoundDomain.com This fix worked for my dimming issues.
