I just did the big 3 and I think the light dim even more!

[stangdriverdoug 10+ year member]

My set up is as follows:

American Bass VFL-120.1 for the subs running 1 ohm

2-12" American Bass XFL

690 CCA stock battery up front

Stinger SPV20 in back

Stock alternator

Old school Kicker 500ss for the high's

0 gauge runs front to back

0 gauge for the sub amp

When I did the big 3 I changed the power and ground wire for the sub amp from 4ga to 0ga, and used 0ga for the big 3. Funny thing is that the lights dim even more now, maybe because I oppened up a bottleneck to the amp. Next step is to upgrade the battery up front and if it's still bad then a new alternator. I don't play it loud that often so hopefully I'll be ok until I get a new alty.

Click to read more...

 

[michaellane 5,000+ posts]

how many watts and what kinda car? also make sure nothing is gorunding out or touching where it shouldnt. guy made a thread like this awhile back where something was touching something it wasnt supposed to when he did the big 3 and had the same problem

 

[350zspl 10+ year member]

your under hood battery is not up for the task , you must replace it

then after you do it might solve you headlight dimming

also the stinger spv20 is the smallest battery stinger makes and only yeilds 300 amps and that is only for a short time after that it yeilds less

i would exchange your underhood battery for a stinger yellow top SPV70 and add 1 more spv20 out back

than you should be fine

 

[stangdriverdoug 10+ year member]

The car is a 98 Lesabre...I think the alt is 140 amp. That VFL-120.1 is 2600 wrms @ 1 ohm with a recommended 150 amp outboard fuse. The difference wasen't dramatic, just slightly more dimming. I did notice slightly more headroom and a little better acccuracy at high volumes after the big 3. Definetly a reccomendation for anything one thinking about it.

 

[Bobby322 10+ year member]

Did you take the stock wiring out? Youre supposed to just go over the stock with with 1/0

 

[stangdriverdoug 10+ year member]

I left the stock wiring in except for the alt to the + battery. If it makes a difference I can add a additional run of 4ga from the alt to the + battery...because thats what was there before.

 

[neverfinished 10+ year member]

no **** its dimming more lol. You took away a bunch of resistance allowing more electricity faster but you dont have the power producing or storing capabilitys to supply this. So now your overstressing your stock alternator/battery and depriving the rest of your cars needs for electricity even more. BTW inconsistent current and/or lack thereof is dangerous to your audio equipment

 

[Alpine4life89 10+ year member]

The car is a 98 Lesabre...I think the alt is 140 amp. That VFL-120.1 is 2600 wrms @ 1 ohm with a recommended 150 amp outboard fuse. The difference wasen't dramatic, just slightly more dimming. I did notice slightly more headroom and a little better acccuracy at high volumes after the big 3. Definetly a reccomendation for anything one thinking about it.

That's your problem right there. You are running 2600 watts to a 140 amp alt. I run 2000 watts to a 220 amp alt and stock battery and get no dimming at all. **** getting a new battery, just upgrade the alt bro.

 

[sub-FATHER 10+ year member]

change your grounds also. from battery to chassis, and chassis to motor.

 

[stangdriverdoug 10+ year member]

yeah ...guess its time for a alternator lol.

 

[S.B.C. 10+ year member]

An alt is good and everything, but youll still need something to hold that power. I wouldnt upgrade front batt, id put one in the back now..

 

[jco1385 5,000+ posts]

 

[RAM_Designs 5,000+ posts]

That VFL-120.1 is 2600 wrms @ 1 ohm with a recommended 150 amp outboard fuse.

The 120.1 does not do 2600 watts, not with a 150 amp fuse at least. To put it in perspective, a Sundown 1500D has a 160 amp fuse rating...as does the new SAE1200D(they both do around 1700-1800, depending on your electrical and ohm load).

 

[stangdriverdoug 10+ year member]

Oh no kidding? I guess it's a very over rated amp then.