Engine Ground big three still dimming??

hey i have a couple thing i want to ask,

i am worried about the ground for the amp since it was close to the spare tire well. i stripped it using a dremel to bare metal and that used a big 14mm bolt with a steel thread to secure it with star washer type lock. it was slight loose but i secured it to the point it was tight.

i do not want to drill another hole, there is a big torx bolt that hold the rear setbelt down, i want to see if i can secure the ground to that and see if it helps any with dimming, i will add the battery if needed, then if that does not cure it, i would like to try a 1/0 run from the front batt to the rear for ground. move the engine to batt 1/0 run and relocate to engine to chassis. i will check resistance before i move the ground at all and then go from there, but i think i need a good solid ground from the front and possibly a small battery or atleast me hopes lol.

my plan is to upgrade on her car to a hid retrofit soon which should lessen the load.

 
It's far more likely that she has a tiny alt that can't keep up.
i respectfully disagree. a 130 amp alt should be enough for that, unless you have a real shitty battery

i used to own a 2000 cougar actually.. thing had so many electrical problems i sold after a year and a half

 
you problem is the ground I would say since you prob connected to the sheet metal of the car and not the actual frame. Connect to the actual frame of the car to see if that helps

 
It's far more likely that she has a tiny alt that can't keep up.
alt is 130 amp i think it should be fine with big three, stinger spv70 battery, and only pushing a jl 1000/1 and 12w7.

i think it is a ground and want to try a run of ground, is it ghetto if i run it from the battery to the rear out the car to test while it is park just throw it over the top and into the hatch to see if it fixes it. i wont be moving at all.

 
alt is 130 amp i think it should be fine with big three, stinger spv70 battery, and only pushing a jl 1000/1 and 12w7.
i think it is a ground and want to try a run of ground, is it ghetto if i run it from the battery to the rear out the car to test while it is park just throw it over the top and into the hatch to see if it fixes it. i wont be moving at all.
lol i used jumper cables runnng outside the car form the trunk to the battery once to test something

 
Not true. I'm about SQ, but depending on my mood or the type of music I enjoy bass applied in extreme amounts.
But anyone who has 1kw+ sub systems and stock main speakers should be shot in the groin to prevent them from breeding.


you are right about the stock speakers but i would rather not be shot in the groin as i am awaiting bad weather. i have a pair of focal polyglass v1 i want to throw in the car but i am also waiting for some raammat and ensolite, overkill.

i already ran the 4 channel rca for the amp and a remote wire as well.

i will hopefully get a kinetik 800 on a trade and slap that in there along withe jl 450/4, a ground wire from the front, deadner in random places, and a pair of 6x8 or 6.5" in the rear.

what do you honestly think in my car i plan to run the 165k2p active of the 450/4 and use a pioneer 880prs to tune it.

On the cougar should i use her stock rear fill and run the polyglass 165vr active off the 450/4. i threw a panasonic in there with crossover, 7 band eq. so i would need to use the slopes and crossover on the amp along with the x10 switch and bandpass.

she wants rear fill and atleast with the headunit i can control the amount of power running to the rear fill.

 
hey guys i just did the big three on my girlfriends car 2000 mercury cougar. i am only running a 12w7 with a 1000/1 v2. i am getting heavy dimming still.
i have

stinger spv70 upfront

1/0 gauge positive run to the back,

1/0 gauge ground in the trunk stripped paint and made a ground

1/0 gauge alternator to batt +

1/0 gauge battery neg to ground (stock ground under battery)

1/0 gauge engine to battery neg(stock)

i left the stock 8 gauge power run from the alt,

i left the stock 8 gauge battery neg to chassis and added a 1/0 gauge, (i did not strip the paint figured the stock ground is good, but now i think about it i will go back and strip it.)

what is weird the stock wiring for engine to ground was 8 gauge and ran from engine to battery terminal neg, i just added a 1/0 gauge run along with it.

should i reroute that to chassis or it is the same since the neg leads to the chassis

before the big three i was getting heavy dimming and voltage drop to around 11.8. usually stayed around 12v-12.7v.

what is my next step,

i was thinking about adding a battery to the back, i have an extra spv70 should i throw it in the back without an isolator and see if it make a difference. i wanted to use a small battery like a kinetik hc800.

i plan to add a jl 450/4 v2 for the highs and focal polyglass component and pair of 6.5" in the rear
hey man I am having the exact same voltage drop in my car.. the exact same. the lowest it will get is 11.8.. on certain songs it stays around 12-12.8 ish. I have a batcap 2000 in the back, both amps grounded to it and the batcap is grounded to the trunk of the car. I just ordered some knu wire to run a ground from the batcap to the front battery instead of grounding in the trunk. soon as I get it and put it in I will let you know if it stabilizes my voltage any.

 
hey man I am having the exact same voltage drop in my car.. the exact same. the lowest it will get is 11.8.. on certain songs it stays around 12-12.8 ish. I have a batcap 2000 in the back, both amps grounded to it and the batcap is grounded to the trunk of the car. I just ordered some knu wire to run a ground from the batcap to the front battery instead of grounding in the trunk. soon as I get it and put it in I will let you know if it stabilizes my voltage any.
I'd recommend leaving the ground in the trunk, adding a run from the front to the rear will help, but it'll be better to leave the original ground in the trunk.

 
it sounds like something is seriously wrong, i have almost 3800 watts rms in my car and i get some dimming with a kinetik 1800 in the back, 2 runs of power in 1/0, everything double grounded in 1/0 and the big 3 in single 1/0. and my alt in only 102 amps. it takes me about 20 seconds of musical bass to dip below 12V i sit at 14.8V full charge.

 
I'd recommend leaving the ground in the trunk, adding a run from the front to the rear will help, but it'll be better to leave the original ground in the trunk.
so what your saying is having 2 main grounds? Leaving the one in the trunk, AND the run from the back to the front?

 
Exactly, your ground in the back might not be as good as you think it is. I had mine grounded in the rear, then added a run of 0/1 ga from the front battery to the rear one and removed the rear ground. After doing this my voltage dropped too low on the big hits, so I put the rear ground back in and the voltage drops stopped.

 
Exactly, your ground in the back might not be as good as you think it is. I had mine grounded in the rear, then added a run of 0/1 ga from the front battery to the rear one and removed the rear ground. After doing this my voltage dropped too low on the big hits, so I put the rear ground back in and the voltage drops stopped.
good deal thanks man. just waiting on this wire and then im all over it. if that doesn't work im going to do what loopkiller told me to try.

 
hey guys weather was a little better still cold and windy but good chance to get couple hours of work in

First thing i did was remove the battery and relocate the engine to chassis wire which use to be setup like the stock 8 gauge running to the negative terminal. Now the engine to chassis is grounded to the chassis at the same location where the stock battery ground is and the additional chassis to battery ground.

So i know have

1/0 gauge from alt to battery fused with 250 amp anl

1/0 gauge from battery to chassis

1/0 gauge from engine to chassis(same grounding point as battery to chassis)

i used a dremel and stripped all the paint in the surrounding area till i saw bare metal and then stripped more lol.

i check resistance on the ground i ran, my multimeter leads show .5ohm with touching the leads together,

when i removed the battery from the car, and checked the ground where i have the big three chassis ground and the ground in the rear. i disconnected the neg from the amp and shoved the lead into the 1/0 gauge. i get around .9ohm-1.1ohm. i figured with the .5 ohm from the lead already that would have my ground with a resistance of .4-.6 ohm.

i think the ground is good and i checked the seat belt bolt and couple other places on the car and all of them showed me the same resistance as my ground. Couple places showed resistance of like 1.5ohm.

i think my ground is goood, i threw a 150amp circuit breaker on the 1/0 gauge wire which runs to the back.

my voltage has stabilized my car starts around 14.3 and then on medium volume i drop to about 13.8-14.

if i have been doing heavy bass notes for like 5 min the voltage stays around 13.5-13.8.

turning on the headlights, ac on full, break light, hazard, bass on full, high beams my voltage drops to about 11.6-12.2.

i know i am gonna throw a battery in the back to stiffen it up and add more reserve.

i have a stinger spv20 coming and i already have a spv 70 sitting.

now this is my girls car and she never even goes past 60% volume, at around 75-80 is when i get heavy drops and dimming.

i do not want to throw such a big battery like the spv70 in the back it will be a waste, i already have a spv70 in the front and thought about throwing a spv20.

here is the info on the battery,

http://www.sonicelectronix.com/item_16771_Stinger+SPV20.html

i figure being a girl and even once i add my jl 450/4 v2, i think the spv20 should take care of her, if it was my car i know i love to jam my **** and i would throw a bigger batt.

what do you guys think and should i throw and isolator or just run it parallel since it is a small batt. I think to help out i might run a 1/0 gauge ground from the front to the back to help out.

so positive from batt to positive on batt in rear, fused twice,

negative from chassis and neg from front batt to rear batt.

 
oh hell yeah **** right the 1000/1 are power hungry,

i am hoping that once i throw a second battery in the back along with another run of ground and actually getting my anl fuseholder and distroblocks.

i have it setup with just a 150 amp fuse upfront,

i would like to setup a 300 amp fuse up front and then 100 amp and 60 amp in the back, after i get the tap from the back battery.

that should help relieve the bottle neck and make it easier for current to flow and have a second battery to stiffen it up. right now my voltage has stablized and tends to stay about 13 as long as i am not bumping extremely hard with all the accessories on. Incase i need i will bump the rear battery to a kinetick 800 or a spv 70.

i am sure i will get the dimming taken care of but it is fun seeing all your improvements by doing the big three, changing grounds or checking resistance. i am eager to see what a second ground to the rear will do and what a battery will do. i would like to have the voltage about 13.8 on hard hits and about 13 with all accessories and a hard bass. right now i dip into 11.7v and want to gain about 1 volt stability from a battery, second ground.

 
I'd recommend adding a 0/1 ga ground from the engine block directly to the chassis. The battery might be a little small for 1000 watts plus everything needed to supply the vehicles demands. Since you already have an extra battery try adding it to the rear with a 1/0 ga run, and see if that helps. If not then the alt might be the problem.
just to clarify that batt is PLENTY big enough for your amp. im using 2 and im running 5kw. my stock battery up front is basically non existent too its pretty muchall the stingers. i do have a 200 amp alt tho but that shouldnt matter. i ram 1000 rms on my stock electrical (130 amp alt, stock batt, no big 3) and had not that bad of dimming.

 
i figured the spv70 up front and a batt half the size of that so a spv 35 would be sufficient for the whole system expecially for a chick lol.

i got a good deal on a spv20 and really don't want to spend any more than i have to knowing she will never even crank the system up. She LOVES the BLUETOOTH handsfree built into the headunit. I do not forsee her cracking up the conversation to listen to the bass in my voice lol.

She usually does not even crank up the bass so while she is in the car there is no dimming. the issue starts when i get in an crank that biatch up, gotta make sure the w7 still pounds lol.

I will keep you up to date what happens once i throw the battery in and the effect of the additional ground.

 
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